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# Energy

### Investigation of Elastic collisions of frictionless gliders

A 0.143 kg glider is moving to the right on a frictionless, horizontal air track with a speed of 0.840 m/s. It has a head-on collision with a 0.303 kg glider that is moving to the left with a speed of 2.25 m/s . Suppose the collision is elastic. Alright, I used the conservation of kinetic energy on this one and I have two var

### Conservation of energy to find height thrown of a ball up

A ball is thrown vertically upwards into the air with a speed of 8.5 m.s-1. Assuming that all of the ball's initial kinetic energy is converted into gravitational potential energy, find the amount by which the height of the ball increases (before it starts to fall again).You should assume g = 9.8 m.s-2 and give your answer to an

### Multiparticle Schrodinger Equation

Please help with the following problem. Two identical spin-1/2 particles with mass m are in a one-dimensional infinite square-well potential with width a, so V(x)=0 for 0 <= x <= a, and there are infinite potential barriers at x=0 and x=a. The particles do not interact with each other; they see only the infinite square-well

### Time dependent perturbation theory problem

A system is in an eigenstate | psi_i > with energy E_i. The perturbation V(t) = H'exp(-((alpha)^2)(t^2)) is turned on at t_i = -infinity and left on until t_f = infinity. Here H' is independent of time, and alpha is a constant. Show that at t_f = infinity, the probability that the system has evolved into the eigenstate |

### Calculate shift produced in the ground-state energy of hydrogen due to the finite size of the proton

In the hydrogen atom, the proton is not really a point charge but has a finite size. Assume that the proton behaves as a uniformly-charged sphere of radius R=10^(-15) m. Calculate the shift this produces in the ground-state energy of hydrogen.

### Simple Harmonic Motion & Elasticity, Reference Circle and Energy

**Please consider significant figures and draw visual graphics** Conceptual Questions: In the figure below, the shadow moves in simple harmonic motion. Where on the shadow's path is (a) the velocity (v) equal to zero and (b) the acceleration (a) equal to zero? **Please note that the velocity (v) and acceleration (a) have th

### Physics of Using Dumbbells

A student sits on a freely rotational stool holding two dumbbells, each of mass 3.00 kg. When the students arms are extended horizontally as in figure, the dumbbells are 1.00 m from the axis of rotation and the student rotates with an angular speed of 0.750 rad/s. The moment of inertia of the student plus stool is 3.00 kg and is

### Distance the block slide up inclined ramp before it comes to rest

Please show your work as I need to understand the solution well. A block of mass 2.0 kg resting on a horizontal frictionless surface is initially held against a spring of constant 5200 N/m that is compressed by 13 cm from its normal length. After the block is released, it slides along the frictionless surface until it encount

### Waves and Atoms

Please show all work and provide justification for answers. 1. Waves show the phenomena of reflection, diffraction, refraction, interference, and absorption. Associate at least one or two of these with each of the following. a. You see a mirage. b. You hear someone whispering just around the corner in the next room.

### Mass-spring system, clock pendulum, submarine sonar echo

1. A mass - spring system in SHM in the horizontal direction. If the mass is 0.25 kg, the spring constant is 12 N/m, and the amplitude is 15 cm, (a) what is the maximum speed of the mass, and (b) where does this occur? (c) What is the speed at half amplitude position? 2. A clock uses a pendulum that is 75 cm long. The clock i

### Mass-spring system, pendulum, oscillator frequency, sound pulses, harmonics

Severe Mental Disorders This question seems to basically be asking for your opinion, so I will try to give you a few ideas about mental disorders that you can expand on. Throughout history, "normal" people who do not have mental disorders have always seemed to be scared or frightened of people who do suffer from mental d

### Brick slides down an incline speed

See attached diagram. The diagrams in Figure 9-13 show a brick weighing 24.8 N being released from rest on a 1.00 m frictionless plane, inclined at an angle of 30.0°. The brick slides down the incline and strikes a second brick weighing 37.4 N. Figure 9-13 (a) Calculate the speed of the first brick at the bottom of the i

### Four problems on electrostatics

#1 A charge of -3.00 nC and a charge of -5.80 nC are seperated by a distance of 50.0 cm. Find the position at which a third charge of +7.50 nC can be placed so that the net electrostatic force on it is zero. #2. A 7.5-nC charge is located 1.8 m from a 4.2-nC charge. Find the magnitude of the electrostatic force that one charg

### Vibrating and Oscillating String

Find the total energy of a vibrating string of length L, fixed at both ends, oscillating in its n'th characteristic mode with and amplitude A. The tension in the string is T and its total mass is M. Hint - consider the integrated kinetic energy at the instant when the string is straight so that it has no stored potential ener

### Impulse, momentum conservation, potential energy

1. Define the term impulse. 2. Using the principle of momentum conservation, explain what happens when a moving billiard ball collides with a stationary ball (cue ball hitting the eight ball). 3. Explain the difference between energy and power and how they are related to work. Give examples of each). 4. A 1000 kilogra

### Kinetic Energy and Potential Energy.

In this simulation, an object traverses the "hills and valleys" of a frictionless roller coaster in the realm of zero air resistance. You will be asked to find measurements and make calculations concerning total mechanical energy and whether it is conserved. Then you will then make some changes to the global air resistance for

### Total Momentum Systems

A 2.3-kg cart is rolling across a frictionless, horizontal track toward a 1.5-kg cart that is held initially at rest. The carts are loaded with strong magnets that cause them to attract one another. Thus, the speed of each cart increases. At a sertain instant before the carts collide, the first cart's velocity is +4.5m/s, and th

### 15 Multiple Choice Questions on Modern Physics - Photons And Photoelectric Effect (Fully Solved and Explained)

1.The wavelength of a photon is 7 x10^-7 m. Calculate the frequency of the photon. Also calculate the energy of the photon in Joules and eV a)4.285 x 10^15 Hertz, 2.84 x 10^-19 Joules, 2.36 eV b)4.285 x 10^15 Hertz, 2.84 x 10^-19 Joules, 1.77 eV c)3.236 x 10^15 Hertz, 3.42 x 10^-19 Joules, 2.36 eV d)3.236 x 10^15 Hertz, 3.4

### A block slides down a large globe starting from the top. To determine the height at which the block leaves the globe and its speed at that moment.

A large globe, with a radius of about 5 m, was built in Italy between 1982 and 1987. Imagine that such a globe has a radius R and a frictionless surface. A small block of mass m slides starts from rest at the very top of the globe and slides along the surface of the globe. The block leaves the surface of the globe when it reache

### Potential energy of the two-spring system; force on the junction point.

The ends of two identical springs are connected. Their unstretched lengths l are negligibly small and each has spring constant k. After being connected, both springs are stretched an amount L and their free ends are anchored at y = 0 and x = +/- L as shown (see attachment). The point where the springs are connected to each othe

### Thermodynamics processes law

The figure below shows how 8 moles of a monatomic ideal gas follows the three-part cycle, the first part of which involves an isothermal expansion from point A, where V = 15 m3, to point B, where V = 90 m3. (a) Provide the missing entries in the following table. Q(J) W(J) &#916;U(J) A>B ____ ___

### Venturi meter to find speed and volume of gas

A venturi meter is a device for measuring the speed of a fluid within a pipe. The drawing shows a gas flowing at a speed v2 through a horizontal section of pipe whose cross-sectional area A2 = 0.0600 m2. The gas has a density of ρ = 1.80 kg/m3. The Venturi meter has a cross-sectional area of A1 = 0.0300 m2 and has been substitu

### Motion of merry-go-round before and after person jumps onto it

A disk-shaped merry-go-round of radius 2.63 m and mass 155 kg rotates freely with an angular speed of .667 rev/s. A 59.4 kg person running tangential to the rim of the merry-go-round at 3.38 m/s jumps onto its rim and holds on. Before jumping on the merry-go-round, the person was moving in the same direction as the merry-go-ro

### Velocity of an object within a pulley system

The system consists of 60-lb and 20-lb blocks A and B, respectively, and 5-lb pulleys C and D that can be treated as thin disks (see the attachment). Determine the speed of block A after block B has risen 5 ft, starting from rest. Assume that the cord does not slip on the pulleys, and neglect the mass of the cord.

### Fermi energy and wavevector for a gas at absolute zero.

Fermi energy and wavevector for a gas at absolute zero.

### Rate of production of heat

1. A certain sedentary person uses energy at an average rate of 123.29Watts. All of this energy has its ultimate origin in the sun. How much matter is converted to energy in the sun per day to supply this person? 2. If 1 kcal = 4.18 kJoule. What is the rate of energy production in kilowatts from a college student producing 1

### Launching of satellite from Earth to Mars.

Assume the Earth has a circular orbit around the sun of radius and that Mars has a circular orbit around the sun of radius . To send a satellite to Mars that requires the least amount of energy the satellite is given an elliptical orbit whose perihelion corresponds to Earth's orbital distance and whose aphelion corresponds to

### Rotational motion and kinetic energy lost

PROBLEM 2: A playground whirl consists of a uniform disk of mass 10M and radius R. It is spinning at a rate of 2.0 rmp. A child mass M, originally at rest, steps on to the whirl. She does not slide back off. What is the final angular velocity of the whirl and the child (assuming the axis is frictionless)? What fractio

### Four problems on rotational dynamics

1) How much work is done by the motor in a CD player to make a CD spin, starting from rest? The CD has a diameter of 12.3 cm and a mass of 15.1 g. The laser scans at a constant tangential velocity of 1.26 m/s. Assume that the music is first detected at a radius of 20.3 mm from the center of the disk. Ignore the small circular ho

### Rydberg Constant for Beryllium

The beryllium (3) ion, Be 3+ is like the hydrogen atom in that it has a single electron. Its emission line spectrum is similar to that of hydrogen, except that the value of the Rydberg constant is different. The following lines were observed for a 'series' (i.e. all have the same value of nf) the Be 3+: 117.18 nm, 80.10nm, 68.35