A hockey puck of mass 0.44 kg is shot west at 2.50 m/s strikes a
second puck, initially at rest, of mass 0.50 kg. As a result of the
collision, the first puck is deflected at an angle of 31° north of
west, with a speed of 1.30 m/s. What is the speed of the second
puck after the collision?
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A uniform 5-m long ladder weighing 80 N leans against a frictionless vertical wall. The foot of the ladder is 1 m from the wall. What is the minimum coefficient of static friction between the ladder and the floor necessary for the ladder not to slip?
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Here we will look at an example of subatomic elastic collisions. High-speed neutrons are produced in a nuclear reactor during nuclear fission processes. Before a neutron can trigger additional fissions, it has to be slowed down by collisions with nuclei of a material called the moderator. In some reactors the moderator consists of carbon in the form of graphite. The masses of nuclei and subatomic particles are measured in units called atomic mass units, abbreviated u, where 1u=1.66×10−27kg. Suppose a neutron (mass 1.0 u) traveling at 2.6×107m/s makes an elastic head-on collision with a carbon nucleus (mass 12 u) that is initially at rest. What are the velocities after the collision? If the neutron's kinetic energy is reduced to 3649 of its initial value in a single collision, what is the mass of the moderator nucleus? Express your answer in atomic mass units as an integer.
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White light (ranging in wavelengths from 380 to 750 nm) is incident on a metal with work function Wo = 2.68 eV.
1. For what range of wavelengths (from lmin to lmax) will NO electrons be emitted?
a) Imin=
b) Imax=
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In a series of experiments, a gas of exotic molecules containing exactly one electron
each is investigated. It is found that:
• When the gas is cold (so all the molecules are in their ground states) and illuminated
with light, it absorbs strongly at wavelengths 103.40nm, 137.87nm and 248.16nm.
• When the gas is cold and illuminated with light of short wavelength, the electrons are
ejected from the molecules as long as the wavelengths is less than 88.63nm.
• When the gas is heated, it emits light with 6 different wavelengths.
(a) If we chose to set the potential energy outside of the molecule to be zero, how far
below zero energy is the ground state of the molecule?
(b) How many discrete energy level does the molecule have?
(c) What wavelengths of light does the heated gas emit?
(d) A free electron with kinetic energy of 2eV is captured by the atom (which is originally ionized) and goes directly into the ground state. What is the wavelength of the emitted photon?
Hint: Electrons can jump from one energy level to another by emitting/absorbing a photon whose energy is equal to the difference in energies between the two states.
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A disk with a c value of 1/2, a mass of 3 kg, and radius of 0.29 meters, rolls without slipping down an incline with has a length of 6 meters and angle of 30 degrees. At the top of the incline the disk is spinning at 28 rad/s. How fast is the disk moving (the center of mass) at the bottom of the incline in m/s?
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A cylinder containing ideal gas is sealed by a piston that is above the gas. The piston is a cylindrical object, with a weight of 36.0 N, which can slide up or down in the cylinder without friction. The inner radius of the cylinder, and the radius of the piston, is 7.00 cm. The top of the piston is exposed to the atmosphere, and the atmospheric pressure is 101.3 kPa. The cylinder has a height of 30.0 cm, and, when the temperature of the gas is 20°C, the bottom of the piston is 14.0 cm above the bottom of the cylinder. (a) Determine the pressure of the gas in the cylinder. kPa (b) Find the number of moles of ideal gas in the cylinder. moles (c) Heat is added, gradually raising the temperature of the gas to 165°C. Calculate the distance between the bottom of the cylinder and the bottom of the piston when the piston comes to its new equilibrium position.
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A 240 g , 25-cm-diameter plastic disk is spun on an axle through its center by an electric motor.
What torque must the motor supply to take the disk from 0 to 1800 rpm in 4.8 s ?
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A 175 g mass is connected to a light spring of force constant 2 N/m that is free to oscillate on a horizontal, frictionless track. The mass is displaced 3 cm from the equilibrium point and released from rest.
a.) Find the period of the motion.
Answer in units of s.
b.) What is the maximum speed of the mass? Answer in units of m/s.
c.)
What is the maximum acceleration of the mass? Answer in units of m/s^2 .
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With the use of a phase shift, the position of an object may be modeled as a cosine or sine function (as a function of time). If given the option, which function would you choose (Note: this is an open-ended question; there is no wrong answer; just be sure to explain your choice please)? Assuming zero phase shift, if you are using a sine function to model the position of an object, what are the initial conditions of the oscillator---that is, the initial position, velocity, and acceleration of the oscillator at t=0? How about if you use a cosine function to model the position?
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The density of gasoline is 7.30 ✕ 102 kg/m3 at 0°C. Its average coefficient of volume expansion is 9.60 ✕ 10−4 (°C)−1, and note that
1.00 gal = 0.00380 m3.
(a) Calculate the mass of 8.3 gal of gas at 0°C. (Give your
answer to at least two decimal places.)
____kg
(b) If 1.000 m3 of gasoline at 0°C is warmed by 20.5°C,
calculate its new volume. (Give your answer to at least two decimal
places.)
____m3
(c) Using the answer to part (b), calculate the density of gasoline
at 20.5°C. (Give your answer to at least three significant
figures.)
____kg/m3
(d) Calculate the mass of 8.3 gal of gas at 20.5°C. (Give your
answer to at least two decimal places.)
____kg
(e) How many extra kilograms of gasoline would you get if you
bought 8.3 gal of gasoline at 0°C rather than at 20.5°C from a pump
that is not temperature compensated?
____kg
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A 10-cm diameter solid metal ball falls through the air at its terminal velocity of 39.3 m/s.
a) What would the new terminal velocity be if the mass of the ball were doubled, while the diameter and all other physical properties of the ball remained unchanged.
b) What would the new terminal velocity be if the diameter of the ball were doubled, while the mass and all other physical properties of the ball remained the same as the original?
c) What would the terminal velocity be for a ball of the same material (and thus same solid density) that has twice the diameter as the original?
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You are designing a high-speed elevator for a new skyscraper. The elevator will have a mass limit of 2400 kg (including passengers). For passenger comfort, you choose the maximum ascent speed to be 18.0 m/s, the maximum descent speed to be 10.0 m/s, and the maximum acceleration magnitude to be 2.70 m/s2. Ignore friction. A). What is the maximum upward force that the supporting cables exert on the elevator car? B). What is the minimum upward force that the supporting cables exert on the elevator car? C). What is the minimum time it will take the elevator to ascend from the lobby to the observation deck, a vertical displacement of 640 m? D).What is the maximum value of a 60.0-kg passenger’s apparent weight during the ascent? E). What is the minimum value of a 60.0-kg passenger’s apparent weight during the ascent? F). What is the minimum time it will take the elevator to descend to the lobby from the observation deck, a vertical displacement of 640 m?
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Respond to the following:
|
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Data & Analysis
Procedure A
Incident Angle 1 |
Refracted Angle 1 |
Incident Angle 2 |
Refracted Angle 2 |
Incident Angle 3 |
Refracted Angle 3 |
90-68 = 22 degrees |
90-74 = 16 degrees |
90-55 = 35 degrees |
90-60 = 30 degrees |
90-44 = 46 degrees |
90-50 = 40 degrees |
Procedure B – concave
Incident Angle 1 |
Refracted Angle 1 |
Incident Angle 2 |
Refracted Angle 2 |
Incident Angle 3 |
Refracted Angle 3 |
99-90 = 9 degrees |
101-90 = 11 degrees |
90-90 = 0 degrees |
90-90 = 0 degrees |
90-80 = 10 degrees |
98-90 = 8 degrees |
Procedure B – convex
Incident Angle 1 |
Refracted Angle 1 |
Incident Angle 2 |
Refracted Angle 2 |
Incident Angle 3 |
Refracted Angle 3 |
96-90 = 6 degrees |
102-90 = 12 degrees |
90-90 = 0 degrees |
90-90 = 0 degrees |
96-90 = 6 degrees |
100-90 = 10 degrees |
Procedure C
Incident Angle 1 |
Refracted Angle 1 |
Incident Angle 2 |
Refracted Angle 2 |
90-60 = 30 degrees |
90-75 = 15 degrees |
90-75 = 15 degrees |
115-90 = 25 degrees |
Procedure D
Focal Point 1 (converging) |
Focal Point 2 (diverging) |
5 cm |
-4.7cm |
Procedure E
The angle of Red is smaller than the angle of Blue.
Procedure F – critical angle
Incident Angle 1 |
90-51 = 39 degrees |
Questions/Applications
HERE IS THE DATA FOR THE QUESTIONS. PLEASE ANSWER THEM FOR ME! THANKS!
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