Answer:
The force at the midpoint of the door.
Explanation:
The torque produced in the door will be:
T = rFsinθ
Here θ = 90 degrees so,
T = rF
At the midpoint of the door the moment arm is half than that of doorknob. So, to produce same torque we have to apply two times force at the midpoint of the door than the force at doorknob.
The correct option is a.
In Physics, the concept of torque shows that the first force at the midpoint of the door has a greater magnitude than the second force at the doorknob, given that the torques are equal and distances from the door h-inge for both forces are different.
Explanation:In the context of torque, the force that one applies on a door at different points creates differing results because of the concept of lever arm. Torque is calculated by multiplying the force applied by the distance from the pivot point, which in this case is the door h-inge. Therefore, if the torques are equal as proposed in the question and the distance for the second force (at the doorknob) from the h-inge is greater than the first force (at the midpoint), it must mean that the magnitude of the second force is less than the first for the torques to be equal. Thus, the first force (at the midpoint) has a greater magnitude.
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2. Why is estimating the number of species on Earth so difficult and why do these estimates vary so greatly?
Answer:
its beacuse there are millions of species in the world, and there are still mooooore speacies we still dont know about. its impossible to study all of them it will take a great amount of time to discover and study them.but, the most mysterious place is the ocean we know more about space than we know about the ocean. the ocean is sooo HUUUUUGGGGGE and massive it covers 70% of the world, imagine how many species will be in a place that covers 70% we still dont know about.
~batmans wife dun dun dun....
Estimating the number of species on Earth so difficult due to man not
discovering all the species on earth yet.
There is a large amount of species yet to be discovered by scientists due to
how big the earth is. The earth comprises of the land and various water
bodies. Most discoveries have been with land organisms as that is where we
live.
In water bodies such as seas, oceans there are many species yet to discover
as they are very large and humans don't live in it giving rise to less
discoveries.
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Imagine a raindrop starting from rest in a cloud 2 km in the air. If it fell with no air friction at all, it would accelerate toward the ground with gravitational acceleration of 9.8m/s2. What would the speed of the drop be when it reached the ground? Convert your answer into miles per hour.
1) 212 mph
2) 433 mph
3) 774 mph
4) 72.5 mph
Answer:
2) 433 mph
Explanation:
The final velocity of the raindrop as it reaches the ground can be found by using the equation for a uniformly accelerated motion:
[tex]v^2 = u^2 + 2ad[/tex]
where
v is the final velocity
u = 0 is the initial velocity (the raindrop starts from rest)
a = g = 9.8 m/s^2 is the acceleration due to gravity
d = 2 km = 2000 m is the distance covered
Solving for v,
[tex]v=\sqrt{u^2 +2gd}=\sqrt{0^2+2(9.8 m/s^2)(2000)}=198 m/s[/tex]
And keeping in mind that
1 mile = 1609 metres
1 hour = 3600 s
The speed converted into miles per hour is
[tex]v=198 \frac{m}{s}\cdot \frac{3600 s/h}{1609 m/mi}=433 mph[/tex]
Christopher came down with chicken pox after spending time in his child's day care. The chicken pox represents what link in the chain of transmission in this scenario? A. Susceptible host B. Infectious agent C. Mode of transmission D. Portal of entry E. Reservoir Reset Next
B the chicken pox is the infectious agent
The separation of white light into its component colors is
a. reflectionb. refractionc. dispersiond. transmission
The dispersion of light occurs when a beam of white light (which is compound of many wavelengths or "colors") is refracted (the different rays of light are diverted depending on their wavelengths) in some medium, leaving their constituent colors separated.
The best known case is when a beam of white light from the sun passes through a prism, thus obtaining rays of different colors like those of the rainbow.
This phenomenom was named by Isaac Newton in the eighteenth century, who performed the experiment explained above.
Hence, the correct option is C.
What are the three main categories of elements?
Answer:
Classification of the Elements. These three groups are: metals, nonmetals, and inert gases.
Explanation:
Answer:If you're referring to Organic Molecules, then they are CARBON, HYDROGEN and OXYGEN.
Explanation:
In each of the parts of this question, a nucleus undergoes a nuclear decay. Determine the resulting nucleus in each case.
A) {\rm ^{227}_{\;\;89}Ac} undergoes alpha decay. Determine the resulting nucleus.
B) {\rm ^{211}_{\;\;83}Bi} undergoes beta-minus decay. Determine the resulting nucleus.
C) {\rm ^{22}_{11}Na} undergoes beta-plus decay. Determine the resulting nucleus.
D) {\rm ^{98}_{43}Tc} undergoes gamma decay. Determine the resulting nucleus.
A) Francium-223
In an alpha decay, a nucleus decay emitting an alpha particle, which corresponds to a nucleus of helium: so, it consists of 2 protons and 2 neutrons.
[tex]X \rightarrow X' + \alpha[/tex]
This means that in the decay:
- The original nucleus loses 2 protons --> so its atomic number Z decreases by 2 units
- The original nucleus loses 2 nucleons (2 protons and 2 neutrons) --> so its mass number A decreases by 4 units
In this example, the original nucleus is Ac (Actinium), with
Z = 89
A = 227
After the decay, it must be
Z - 2 = 89 - 2 = 87
A - 4 = 227 - 4 = 223
We see from the periodict table, Z=87 corresponds to Francium (Fr), so the final nucleus will be francium-223 (the isotope of francium with 223 nucleons).
B) Polonium-211
In a beta-minus decay, a neutron in the nucleus turns into a proton, emitting a fast-moving electron (the beta particle) and an anti-neutrino.
[tex]n \rightarrow p + e^- + \bar{\nu}[/tex]
Therefore, in this process:
- The original nucleus gains 1 protons, so its atomic number Z increases by 1 unit
- The original nucleus does not lose/gain nucleons, so its mass number A remains the same
In this example, the original nucleus is Bi (bismuth)-211, with
Z = 83
A = 211
So After the decay, it will be
Z + 1 = 83 + 1 = 84
A = 211
So, the nucleus will be Polonium (Z=84), isotope with 211 nucleons.
C) Neon-22
In a beta-plus decay, a proton in the nucleus turns into a neutron, emitting a fast-moving positron (the beta particle) and a neutrino.
[tex]p \rightarrow n + e^+ +\nu[/tex]
Therefore, in this process:
- The original nucleus loses 1 protons, so its atomic number Z decreases by 1 unit
- The original nucleus does not lose/gain nucleons, so its mass number A remains the same
In this example, the original nucleus is Na (sodium)-22, with
Z = 11
A = 22
So After the decay, it will be
Z - 1 = 11 - 1 = 10
A = 22
So, the nucleus will be Neon (Z=10), isotope with 22 nucleons.
D) Technetium-98
In a gamma decay, an unstable nucleus emits a gamma ray:
[tex]X' \rightarrow X + \gamma[/tex]
In this process, only energy is released (in the form of gamma ray), so there is no gain/loss of protons/neutrons in the process. This means that:
- The atomic number Z remains constant
- The mass number A remains constant
In this example, we have a nucleus of Tc (Technetium)-98, with
Z = 43
A = 98
These numbers will not change during the decay: this means that after the decay, we will still have a nucleus of Technetium-98.
How will a current change if the voltage in a circuit is held constant while the resistance doubles?
The current will drop to half of its original value.
Explanation:To solve this problem, we must use Ohm's law that states that in a circuit the voltage [tex]v[/tex] across a resistor is directly proportional to the current that flows through that circuit. In other words:
[tex]v \propto Ri \\ \\ or: \\ \\ v=Ri \\ \\ It's \ also \ valid: i=\frac{v}{R}[/tex]
According to our problem, if the voltage in the circuit is held constant while the resistance double, that is [tex]R_{New}=2R \ and \ v_{New}=v[/tex]. So:
[tex]v=R_{New}i_{New} \\ \\ v=2Ri_{New} \\ \\ Isolating \ i_{New}: \\ \\ i_{New}=\frac{v}{2R} \therefore i_{New}=\frac{1}{2}\frac{v}{R} \therefore i_{New}=\frac{1}{2}i[/tex]
In conclusion, the current will drop to half of its original value.
Select the correct answer. Veins carry blood from the capillaries to the venules. A. True B. False
Answer:
false
Explanation:
veins carry blood towards the heart after blood passes through the capillaries.
Answer:
False
Explanation:
Veins are vessels that carry deoxygenated blood back to the heart.
Which types of electromagnetic waves have wavelengths that are longer than those of visible light but shorter than those of microwaves? gamma rays X-rays infrared light radio waves
Answer:
Infrared
Explanation:
An electromagnetic spectrum is an arrangement of electromagnetic waves in order of increasing frequency and decreasing wavelengths.The spectrum ranges from gamma rays which have the highest frequency and the shortest wavelength to radio waves which have the longest wavelength and the lowest frequency and energy.Other electromagnetic waves in the spectrum are, microwaves, infrared, Visible light, ultra-violet radiation and X-rays.The infrared light of electromagnetic wave has wavelength that is longer than the visible light but shorter than the microwave.Answer:
Infrared
Explanation:
Jason fought in the war in Iraq and witnessed some horrific sights. When he got home from the war, Jason didn't seem to remember these shocking events anymore. What happened?
Jason probably has repressed the memories.
Jason's experiences were stored in his false memory.
Jason has amnesia.
Answer:
Jason has repressed the memories
Explanation:
Answer:
Jason has amnesia.
Explanation:
Amnesia is a kind of memory loss. Some people cannot learn new things and this is known as anterograde amnesia. Some people forget events from their past and this is called as retrograde amnesia. Jason has retrograde amnesia because he has forgotten his past events. The causes for this disease are given below:
i) Brain injuries
ii) Certain drugs and alcohol
iii) Traumatic events
The impulse experienced by a body is equivalent to the body’s change in
Momentum
Explanation:The momentum of a particle is defined as the product of the particle mass and the particle velocity as follows:
[tex]\overrightarrow{p}=m\overrightarrow{v}[/tex]
On the other hand, the impulse of a constant force is defined as:
[tex]\overrightarrow{J}=\varSigma\overrightarrow{F}(t_{2}-t_{1})=\varSigma\overrightarrow{F}\Delta t[/tex]
We also know that the net force acting on a particle equals the rate of change of the particle’s momentum, so:
[tex]\varSigma\overrightarrow{F}=m\overrightarrow{a}=m\frac{d}{dt}(\overrightarrow{v})=\frac{d}{dt}(m\overrightarrow{v})=\frac{d\overrightarrow{p}}{dt}[/tex]
If the force is constant, then [tex]\frac{d\overrightarrow{p}}{dt}[/tex] equals the total change in momentum over a period of time:
[tex]\varSigma\overrightarrow{F}=\frac{\overrightarrow{p_{2}}-\overrightarrow{p_{1}}}{t_{2}-t_{1}} \\ \\ \varSigma\overrightarrow{F}(t_{2}-t_{1})=\overrightarrow{p_{2}}-\overrightarrow{p_{1}} \\ \\ \boxed{\overrightarrow{J}=\Delta \overrightarrow{p}}[/tex]
The impulse experienced by a body is equivalent to its change in momentum. This principle is based on Newton's second law of motion. Impulse is the product of the force and the duration over which it is applied.
Explanation:The impulse experienced by a body is equivalent to the body’s change in momentum. This principle is based on Newton's second law, which in terms of momentum states that the net force applied to a system equals the rate of change of the momentum that the force causes. In simpler terms, when a force is applied on an object for a certain amount of time, the object experiences an impulse. This impulse is the difference between the initial and final momentum of the object.
For example, consider a ball bouncing off a floor. If the force of the floor on the ball is constant over a specific duration, then the resulting impulse or change in momentum can be calculated by multiplying the force by the duration of the force application. So, an impulse can cause the object's motion to change due to the effect it has on the ball's momentum.
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What is the longest wavelength light capable of ionizing a hydrogen atom in the ground state?
Answer:
[tex]9.12\cdot 10^{-8} m[/tex]
Explanation:
The energy needed to ionize a hydrogen atom in the ground state is:
[tex]E=13.6 eV= 2.18\cdot 10^{-18}J[/tex]
The energy of the photon is related to the wavelength by
[tex]E=\frac{hc}{\lambda}[/tex]
where
h is the Planck constant
c is the speed of light
[tex]\lambda[/tex] is the wavelength
Solving the formula for the wavelength, we find
[tex]\lambda=\frac{hc}{E}=\frac{(6.63\cdot 10^{-34} Js)(3\cdot 10^8 m/s)}{2.18\cdot 10^{-18}J}=9.12\cdot 10^{-8} m[/tex]
Final answer:
The longest wavelength of light that can ionize a hydrogen atom in its ground state is approximately 91.2 nanometers (nm), which falls in the ultraviolet range of the electromagnetic spectrum.
Explanation:
The longest wavelength light capable of ionizing a hydrogen atom in the ground state is associated with the energy required to remove an electron from a hydrogen atom that is in its ground state (n=1). In physics, the process of ionization involves providing enough energy to an atom to remove its electron. The energy of a photon of light is inversely proportional to its wavelength, according to the relationship E = hc/λ, where E is the energy, h is Planck's constant, c is the speed of light, and λ is the wavelength.
The energy required to ionize hydrogen from the ground state is 13.6 eV, which is the ionization energy of hydrogen. We can calculate the longest wavelength of light capable of ionizing hydrogen using the formula λ = hc/E. The constant values are h = 6.626 x 10-34 J·s, and c = 3 x 108 m/s. Therefore, the longest wavelength, λ, is given by λ = (6.626 x 10-34 J·s * 3 x 108 m/s) / (13.6 eV * 1.602 x 10-19 J/eV), which calculates to approximately 91.2 nm.
Thus, the longest wavelength of light that can ionize hydrogen in its ground state is about 91.2 nanometers (nm), which falls in the ultraviolet (UV) range of the electromagnetic spectrum.
Orbital velocity is the average speed ofa planet moving through space in itsorbit around the sun. Which of thefollowing planets has the fastestorbital velocity?A MercuryB JupiterC MarsD Pluto
Answer:
Mercury
Explanation:
The force of gravity is equal to the mass times the centripetal acceleration:
Fg = m v² / r
Also, the force of gravity is defined by Newton's law of universal gravitation, which states the Fg = mMG / r², where m and M are the masses of the objects, G is the universal constant of gravitation, and r is the distance between the objects.
mMG / r² = m v²/ r
MG / r = v²
This means the square of the orbital velocity is equal to the mass of the sun times the universal constant of gravity divided by the orbital radius. So whichever planet has the smallest orbital radius will have the highest orbital velocity. Of the four options, that would be Mercury.
which unit describes the amount of potential energy that each charge has in a circuit?
A.Voltage
B.Resistance
C.Current
D.Power
Answer:
I believe the answer is A. Voltage
Explanation:
Answer:
[tex]A. Voltage[/tex]
Explanation:
As we know that electric potential is defined as the work done to move a unit charge from one potential to other potential.
Here the unit charge is moved from lower potential to higher potential then in that case the work done to move the charge is stored in the form of potential energy
this is given as
[tex]V = \frac{W}{q}[/tex]
so here we can say that the correct answer for the amount of potential energy for each charge is given as
[tex]A. Voltage[/tex]
Please help on this one?
the upside down image means an inverted image and for an inverted image, magnification is negative
so the answer is -m
The coefficient of static friction between waxed skis and now snow is 0.14. What force will be needed to get a 700 N skier at rest moving?
A: 28 N
B: 70 N
C: 98 N
D: 980 N
Answer:
C. 98 N
Explanation:
The force needed to get the skier at rest moving must be at least equal to the maximum static frictional force acting on the skier, which is given by
[tex]F=\mu W[/tex]
where
[tex]\mu = 0.14[/tex] is the coefficient of static friction
W = 700 N is the weight of the skier
Substituting into the equation, we find
[tex]F=(0.14)(700 N)=98 N[/tex]
Answer:
c
Explanation:
μ = f/N where μ is the coefficient of friction; f is the amount of force that resists motion, and N is the normal force. You must solve for f here so 700 N x .14 = 98 N.
Suppose a bicycle was coasting on a level surface, and there was no friction. What would happen to the bicycle?
If there is no friction and no horizontal force acting on the bicycle, then the bicycle keeps rolling at a constant speed in a straight line, until the cows come home, Dante's Inferno freezes over, and the POTUS accepts some responsibility for his words, actions, and consequences.
Answer:
It would keep going at constant speed.
Explanation:
an object is placed along the principal axis of a thin converging lens that has a focal length of 14 cm. if the distance from the object to the lens is 21 cm, what is the distance from the image to the lens
Answer:
42 cm
Explanation:
For a converging lens, the focal length is positive:
f = +14 cm
In this problem, the distance of the object from the lens is 21 cm:
p = +21 cm
The distance of the image from the lens can be found by using the lens equation:
[tex]\frac{1}{f}=\frac{1}{p}+\frac{1}{q}[/tex]
where q is the image distance. Solving the formula for q and substituting the numbers, we find
[tex]\frac{1}{q}=\frac{1}{f}-\frac{1}{p}=\frac{1}{14 cm}-\frac{1}{21 cm}=\frac{1}{42 cm}\\q= 42 cm[/tex]
Which scientist’s notebooks are still too radioactive to handle?
Explanation:
Marie Curie's notebooks, as well as all of her belongings, including her clothes, were contaminated with ionizing radiation. In fact, also those of her husband, because this couple of scientists discovered the radioactivity of several elements, helping the advance of science, but did not know about the consequences of dealing with these materials without adequate protection.
It should be noted that Curie's notes are stored in the basements of the National Library of France, stored in thick lead boxes and those who wish to access these documents must follow the appropriate protocol to treat radioactive material, wear appropriate clothing and sign a responsibility agreement before allowing them to review the documents.
Person X pushes twice as hard against a stationary brick wall as person Y. Which one of the following statements is correct?
A) Both do positive work, but person X does four times the work of person Y.
B) Both do positive work, but person X does twice the work of person Y.
C) Both do the same amount of positive work.
D) Both do zero work.
E) Both do positive work, but person X does one-half the work of person Y.
Answer:
D) Both do zero work
Explanation:
The work done by a force is given by:
[tex]W=Fd cos \theta[/tex]
where
F is the force applied
d is the displacement
[tex]\theta[/tex] is the angle between the direction of the force and the displacement
From the formula, we notice that work is done online when the displacement is non-zero, so when the object is moving.
In this problem, the wall is stationary: this means that the displacement is zero, d = 0, so no work is done.
Even though Person X is pushing twice as hard as Person Y, both of them are doing zero work, because the brick wall is not moving. Thus, the displacement is zero, and the work done, according to the Physics formula, is also zero.
Explanation:The correct answer is D) Both do zero work.
According to the concept of work in Physics, work is defined as the amount of energy transferred by a force over a displacement. It is given by the formula Work = Force x Distance x cosθ. Here, even though Person X is pushing twice as hard, the brick wall isn't moving (i.e., displacement is zero). When the displacement is zero, no matter how much force is applied the work done will be zero because the distance over which the force is applied is zero. Therefore, both Person X and Person Y are doing zero work.
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An incompressible fluid flows steadily through a pipe that has a change in diameter. The fluid speed at a location where the pipe diameter is 8.0 cm is 1.28 m/s. What is the fluid speed at a location where the diameter has narrowed to 4.0 cm?
Answer:
5.10 m/s
Explanation:
The volumetric flow rate for an incompressible fluid through a pipe is constant, so we can write:
[tex]A_1 v_1 = A_2 v_2[/tex] (1)
where
[tex]A_1[/tex] is the cross-sectional area of the first part of the pipe
[tex]A_2[/tex] is the cross-sectional area of the second part of the pipe
[tex]v_1[/tex] is the speed of the fluid in the first part of the pipe
[tex]v_2[/tex] is the speed of the fluid in the second part of the pipe
Here we have:
[tex]v_1 = 1.28 m/s[/tex]
[tex]r_1 = \frac{8.0 cm}{2}=4.0 cm = 0.04 m[/tex] is the radius in the first part of the pipe, so the area is
[tex]A_1 = \pi r_1^2 = \pi (0.04 m)^2 =5.02\cdot 10^{-3}m^2[/tex]
[tex]r_2 = \frac{4.0 cm}{2}=2.0 cm = 0.02 m[/tex] is the radius in the first part of the pipe, so the area is
[tex]A_2 = \pi r_2^2 = \pi (0.02 m)^2 =1.26\cdot 10^{-3}m^2[/tex]
Using eq.(1), we find the fluid speed at the second location:
[tex]v_2 = \frac{A_1 v_1}{A_2}=\frac{(5.02\cdot 10^{-3} m^2)(1.28 m/s)}{1.26\cdot 10^{-3} m^2}=5.10 m/s[/tex]
The fluid speed at a location where the diameter has narrowed to 4.0 cm is 5.12 m/s
[tex]\texttt{ }[/tex]
Further explanationThe basic formula of pressure that needs to be recalled is:
Pressure = Force / Cross-sectional Area
or symbolized:
[tex]\large {\boxed {P = F \div A} }[/tex]
P = Pressure (Pa)
F = Force (N)
A = Cross-sectional Area (m²)
Let us now tackle the problem !
[tex]\texttt{ }[/tex]
Given:
diameter of pipe at location 1 = d₁ = 8.0 cm
speed of fluid at location 1 = v₁ = 1.28 m/s
diameter of pipe at location 2 = d₂ = 4.0 cm
Asked:
speed of fluid at location 2 = v₂ = ?
Solution:
We will use Continuity Equation as follows:
[tex]A_1 v_1 = A_2 v_2[/tex]
[tex]\frac{1}{4}\pi (d_1)^2 v_1 = \frac{1}{4} \pi (d_2)^2 v_2[/tex]
[tex](d_1)^2 v_1 = (d_2)^2 v_2[/tex]
[tex]v_2 = (\frac{d_1}{d_2})^2 v_1[/tex]
[tex]v_2 = (\frac{8}{4})^2 \times 1.28[/tex]
[tex]v_2 = 2^2 \times 1.28[/tex]
[tex]v_2 = 4 \times 1.28[/tex]
[tex]v_2 = 5.12 \texttt{ m/s}[/tex]
[tex]\texttt{ }[/tex]
Learn moreMinimum Coefficient of Static Friction : https://brainly.com/question/5884009The Pressure In A Sealed Plastic Container : https://brainly.com/question/10209135Effect of Earth’s Gravity on Objects : https://brainly.com/question/8844454[tex]\texttt{ }[/tex]
Answer detailsGrade: High School
Subject: Physics
Chapter: Pressure
[tex]\texttt{ }[/tex]
Keywords: Gravity , Unit , Magnitude , Attraction , Distance , Mass , Newton , Law , Gravitational , Constant , Liquid , Pressure
Two very small spherical metal objects, each with 1 coulomb of charge, are brought together in a vacuum so that the separation distance between their centers is 1 mm. what is the force of repulsion between the two object? (coulomb's constant is k=9.0 × 109 n.m2/c2.)
Answer: 9*10^15 N
Force=kqq/r^2
F=[(9*10^9)(1)(1)]/.001^2=9.0*10^15
Answer:
The force of repulsion between the two object is 9*10¹⁵ N
Explanation:
Coulomb's law indicates that charged bodies suffer a force of attraction or repulsion when approaching. The value of said force is proportional to the product of the value of its loads and inversely proportional to the square of the distance that separates them. This is expressed mathematically by the expression:
[tex]F=K*\frac{Q*q}{r^{2} }[/tex]
where:
F is the electrical force of attraction or repulsion. In the International System it is measured in Newtons (N). Q and q are the values of the two point charges. In the International System they are measured in Culombios (C). r is the value of the distance that separates them. In the International System it is measured in meters (m). K is a constant of proportionality called constant of Coulomb's law. It depends on the medium in which the loads are located. For vacuum K is approximately 9*10⁹ [tex]\frac{N*m^{2} }{C^{2} }[/tex] in the International System.From this law it is possible to predict the electrostatic force of attraction or repulsion between two particles according to their electrical charge and the distance between them.
The force will be of attraction if the charges are of opposite sign and of repulsion if they are of the same sign.
In this case:
Q=q= 1 Cr=1 mm= 0.001 mThen:
[tex]F=9*10^{9} \frac{N*m^{2} }{C^{2} } *\frac{1 C*1C}{(0.001m)^{2} }[/tex]
So:
F=9*10¹⁵ N
The force of repulsion between the two object is 9*10¹⁵ N
A hockey puck is set in motion across a frozen pond. If ice friction and air resistance are neglected, the force required to keep the puck sliding at constant velocity is A) zero. B) equal to its weight divided by its mass. C) equal to the product of its mass times its weight.
Answer:
Zero
Explanation:
According to Newton's second law, the net force acting on an object is equal to the product between the object's mass and its acceleration:
F = ma
For the hockey puck, there are no forces acting on it during its motion, since ice friction and air resistance are negligible. This means that the net force is zero:
F = 0
But this means that the acceleration is also zero:
a = 0
So the hockey puck is moving already at constant velocity. Therefore, there is no need for additional forces.
Final answer:
The force required to maintain a hockey puck's constant velocity across a frictionless ice pond, where air resistance is also neglected, is zero, in accordance with Newton's first law of motion.
Explanation:
The question pertains to dynamics in classical mechanics, specifically to Newton's first law of motion which states that an object in motion will remain in motion at a constant velocity if no net external force acts upon it. Since the question specifies a scenario where air resistance and ice friction are neglected, the force required to keep the puck sliding at constant velocity is zero. This is because there are no external forces acting on the puck to change its state of motion.
In a hypothetical frictionless environment, once the hockey puck is set in motion, it does not require any additional force to maintain its velocity due to the absence of resistive forces such as friction and air resistance. Indeed, this is an idealized situation, but it helps us understand the principle that, without external forces, a moving object will continue to move at a constant speed and direction.
About 0.1 eV is required to break a "hydrogen bond" in a protein molecule. Calculate the minimum frequency and maximum wavelength of a photon that can accomplish this.minimum frequencyHzmaximum wavelengthm
Answer:
Frequency: [tex]2.41\cdot 10^{13}Hz[/tex], Wavelength: [tex]1.24\cdot 10^{-5}m[/tex]
Explanation:
The energy of the photon is equal to the energy required to break the bond, so 0.1 eV.
First of all, we need to convert the energy of the photon from eV to Joule:
[tex]E=0.1 eV \cdot (1.6\cdot 10^{-19}J/eV)=1.6\cdot 10^{-20} J[/tex]
The energy of the photon is related to its frequency by:
[tex]E=hf[/tex]
where h is the Planck constant and f is the frequency.
Solving for f,
[tex]f=\frac{E}{h}=\frac{1.6\cdot 10^{-20}J}{6.63\cdot 10^{-34}Js}=2.41\cdot 10^{13}Hz[/tex]
The wavelength instead is given by
[tex]\lambda=\frac{c}{f}[/tex]
where c is the speed of light. Substituting,
[tex]\lambda=\frac{3\cdot 10^8 m/s}{2.41\cdot 10^{13} Hz}=1.24\cdot 10^{-5}m[/tex]
The minimum frequency required to break a hydrogen bond in a protein molecule is approximately[tex]\(2.4 \times 10^{13}\)[/tex] Hz, and the maximum wavelength of a photon that can accomplish this is approximately[tex]\(1.2 \times 10^{-5}\)[/tex] m.
To calculate the minimum frequency of a photon that can break a hydrogen bond in a protein molecule, we use the energy of a photon given by the equation [tex]\(E = h \nu\),[/tex]where E is the energy of the photon, (h) is Planck's constant, and [tex]\(\nu\)[/tex] is the frequency. We can rearrange this equation to solve for the frequency:
[tex]\[\nu = \frac{E}{h}\][/tex]
Given that [tex]\(E = 0.1\) eV[/tex], we first convert this energy to joules (J), knowing that 1 eV is equivalent to[tex]\(1.602 \times 10^{-19}\) J:[/tex]
[tex]\[E = 0.1 \times 1.602 \times 10^{-19} \text{ J} = 1.602 \times 10^{-20} \text{ J}\][/tex]
Now, using Planck's constant[tex]\(h = 6.626 \times 10^{-34}\)[/tex] J·s, we can find the minimum frequency:
[tex]\[\nu = \frac{1.602 \times 10^{-20} \text{ J}}{6.626 \times 10^{-34} \text{ J}} =2.416 \times 10^{13} \text{ Hz}\][/tex]
We can rearrange this equation to solve for the wavelength:
[tex]\[\lambda = \frac{c}{\nu}\][/tex]
Using the speed of light [tex]\(c = 3 \times 10^8\) m/s,[/tex] we can find the maximum wavelength:
[tex]\[\lambda = \frac{3 \times 10^8 \text{ m/s}}{2.416 \times 10^{13} \text{ Hz}} =1.243 \times 10^{-5} \text{ m}\][/tex]
The human eye can respond to as little as 10^-18J of light energy. For a wavelength at the peak of visual sensitivity, 550 nm, how many photons lead to an observable flash?
Answer:
Approximately 3 photons
Explanation:
The energy of a photon at the peak of visual sensitivity is given by:
[tex]E=\frac{hc}{\lambda}[/tex]
where
h is the Planck constant
c is the speed of light
[tex]\lambda=550 nm = 5.5\cdot 10^{-7}m[/tex] is the wavelength of the photon
Substituting into the formula,
[tex]E_1=\frac{(6.63\cdot 10^{-34} Js)(3\cdot 10^( m/s)}{5.50\cdot 10^{-7} m}=3.6\cdot 10^{-19} J[/tex]
This is the energy of one photon. The human eye can detect an amount of energy of
[tex]E=10^{-18} J[/tex]
So the amount of photons contained in this energy is
[tex]n=\frac{E}{E_1}=\frac{10^{-18} J}{3.6\cdot 10^{-19}J}=2.8 \sim 3[/tex]
so approximately 3 photons.
A ray of light traveling in air strikes the surface of water at an angle of incidence of 35 degrees. Calculate the angle of refraction of the light in water. Index of refraction of water is 1.33, while that for air is 1.00.
Remember to identify all of your data, write the equation, and show your work.
Answer:
[tex]25.5^\circ[/tex]
Explanation:
To calculate the angle of refraction you can use Snell's law:
[tex]\text{n}_1*\sin\theta_1 = \text{n}_2*\sin\theta_2[/tex]
With what we have:
[tex]\text{n}_1 =1\\\text{n}_2= 1.33\\sin\theta_1 = 35^\circ\\sin\theta_2=x[/tex]
[tex]\therefore 1 *sin35^\circ =1.33*sin\theta_2\\\\sin\theta_2=\frac{1 *sin35^\circ}{1.33}\\\\\theta_2=\sin^{-1}(\frac{1 *sin35^\circ}{1.33})\\\\\theta_2= 25.5476^\circ\approx 25.5^\circ[/tex]
The angle of refraction of light in water can be calculated using Snell's Law, which compares the angles of incidence and refraction and the refractive indices of the two media. In this case, the angle of refraction is approximately 23 degrees.
Explanation:The angle of refraction of light can be calculated using Snell's Law which states that the ratio of the sine of the angle of incidence to the sine of the angle of refraction is equal to the ratio of the refractive indices of the two media.
In this case, the angle of incidence is 35 degrees, the refractive index of air is 1.00, and the refractive index of water is 1.33.
Using the formula:
sin(angle of incidence) / sin(angle of refraction) = (refractive index of air) / (refractive index of water)
We can solve for the angle of refraction:
sin(35) / sin(angle of refraction) = 1.00 / 1.33
Simplifying the equation, we find that the angle of refraction is approximately 23 degrees.
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Why do thunderstorms most often occur in the summer months?
Answer:
Because moisture and warmth are crucial to thunderstorms
Due tomorrow pls help.
Review the properties of meters used in electric circuits by placing an X in the correct column.
Answer:
Ammeter:
- measures current
-connected in series
-measurement expressed in amperes
-measures the amount of charge per second passing through
The rest is for voltmeter
Explanation:
Properties of an Ammeter:
Measures current.Connected in series.Measurement expressed in amperes.Measures the amount of charge per second passing through.Properties of a Voltmeter:
Measures potential difference.Connected in parallel.Measurement expressed in volts.Measures the change in energy per unit charge between two points.What is an Ammeter?An ammeter is a device which used to measure the electric current in a circuit.The SI unit of electric current is Amperes (A).The ammeter is usually connected in series to measure the current. An ammeter usually has low resistance so that it does not cause a significant voltage drop in the circuit being measured.What is Voltmeter?A voltmeter is a device which used for measure the electric potential difference between two points in an electric circuit.It is connected in parallel.The SI unit of potential difference or voltage is Volts (V).It usually has a high resistance so that it takes negligible current from the circuit.Learn more about resistance for an ideal ammeter and voltmeter here -https://brainly.com/question/82784
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A measure of the average kinetic energy of the individual particles in an object is called
Temperature is a physical quantity that reflects the amount of heat in a body or medium. This amount of heat is related to the internal energy of a system (thermodynamically speaking), according to the movement (speed) of each of the particles that compose it, this means that it is related to its kinetic energy.
Therefore, the higher the kinetic energy, the higher the thermal energy in the system and the higher the temperature.
Answer:
All matter is made up of tiny particles. These particles are always moving even if the matter they make up is stationary. Recall that the energy motion is called kinetic energy. So all particles of matter have kinetic energy. Temperature is a measure of the average kinetic energy of the individual particles in matter.
Explanation:
The full range of frequencies of electromagnetic radiation is called
The electromagnetic spectrum is the set of electromagnetic radiations distributed in their different frequencies or wavelengths, which in turn are related to their energy.
If we go from the smallest wavelengths known up to now (because according to physics the electromagnetic spectrum is infinite and continuous) to the longest, the electromagnetic spectrum covers the following radiations:
Gamma rays, X-rays, ultraviolet, visible light (all the colors we are able to see), infrared, radio waves and microwaves.
Where those with shorter wavelength (or higher frequency) have more energy than those with a longer wavelength.
The electromagnetic spectrum encompasses all wavelengths and frequencies of electromagnetic radiation, including radio waves and gamma rays.
Electromagnetic spectrum refers to the full range of wavelengths or frequencies of electromagnetic radiation.
The electromagnetic spectrum covers wavelengths from radio waves to gamma rays, including visible light, infrared, and ultraviolet light.
The relationship between frequency and wavelength is key in understanding the electromagnetic spectrum.