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# Conservation of Energy

### Bullet Motion and Conservation of Energy

A bullet with a mass of 45 g is fired upward through a hole in a table into a block of wood with a mass of 5.2 kg. The bullet lodges in the block and the two rise to a height of 3.1 m above the table. 1. Calculate the potential energy of the block above the table. 2. Calculate kinetic energy and velocity of the block as it

### Calculating horizontal distance

A shotputter throws the shot (mass = 7.3 kg) with an initial speed of 14m/s at a 40* angle to the horizontal. Calculate the horizontal distance traveled by the shot if it leaves the athlete's hand at a height of 2.2 m above the ground.

### Principle of energy conservation.

A 2.4 kg block is dropped on to a spring of spring constant 3995 N/m from a height of 5.0 m. When the block is momentarily at rest, the spring has been compressed by 25 cm. Find the speed of the block when the compression of the spring is 15 cm. Use the principle of energy conservation in the analysis and solution.

### X-Ray Problem

An X-ray photon of wavelength 6 pm (1 pm = 10^-12 m) makes a head-on collision with an electron, so that the scattered photon goes in a direction opposite to that of the incident photon. The electron is initially at rest. (a) How much longer is the wavelength of the scattered photon than that of the incident photon? (b) W

### Work, Kinetic Energy, and Potential Energy

See attached file.

### Shortest path between two points in polar coordinates

Show that the shortest path between two given points in a plane is a straight line, using plane polar coordinates.

### Velocities, distances by Law of conservation of Energy.

Q. Bouncing a ball: Let g be the acceleration of gravity near the Earth's surface. The acceleration of gravity near the surface of the Moon is (approximately) g/6. Using the law of conservation of energy, i.e. the principle of conservation of energy, solve the following. (a) Suppose that a ball is dropped from 9 feet above

### Problem on frictionless movement of a particle

A particle, starting from point A in the drawing, is projected down the curved runway. Upon leaving the runway at point B, the particle is traveling straight upward and reaches a height of 4.00 m above the floor before falling back down. Ignoring friction and air resistance, what is the speed f the particle at point A? See at

### the collision between a ball and the ground

A ball is dropped from rest at the top of a 6.10 m tall building, falls straight downward, collides inelastically with the ground, and bounces back. The ball loses 10.0% of its kinetic energy every time it collides with the ground. How many bounces can the ball make and still reach a windowsill that is 2.44 m above the grou

### collision between a bullet and a wooden block of a pendulum

A 2.50 g bullet, traveling at a speed of 425 m/s, strikes the wooden block of a ballistic pendulum. The block has a mass of 215 g. (a)What is the speed of the bullet/block combination immediately after the collision. (b)How high does the combination rise above its initial position?

### Conservation of Momentum and Relativity

An electron moving in the positive x-direction is characterized by GAMMA = 1000 and BETA = 1 - 5 x 10^-7 which for this problem you can take as 1. A photon of energy h&#957;, traveling at 45 degrees with respect to the x axis collides with the electron. The collision results in the creation of an electron-positron pair plus an

### Lagrangian and Hamiltonian dynamics of a particle

A particle of mass m moves in one dimension under the influence of a force: F(x, t) = (k/x^2)*e^(-t/T) Where k and T are positive constants. a) Compute the Lagrangian and Hamiltonian Functions b) Compare the Hamiltonian and the total energy. c) Discuss the conservation of energy for the system.

### basic conservation devices

The first energy crisis in the U.S occurred in 1973. In response many new devices were created and many installed. Today, companies appear to be disinterested in energy conservation despite the rule of thumb that 50% of the energy expense can be saved with basic conservation devices. Why would companies not be interested in avoi

### Physics questions

28-A 7.0 g bullet is fired into a 1.5 kg ballistic pendulum. The bullet emerges from the block with a speed of 200 m/s, and the block rises to a maximum height of 12 cm. Find the initial speed of the bullet? 18- A 730 N man stands in the middle of a frozen pond of radius 5.0 m. He is unable to get to the other side because o

### Velocity of an electron

2 stationary point charges +3.00 nC and +2.00 nC are seperated by a distance of 50.0 cm. An electron is released from rest at a point midway between the two charges and moves along the line connecting the two charges. What is the speed of the electron when it is 10.0 cm from the +3.00 nC charge?

### If the lower layer of the liquid in the graduated

1. If the lower layer of the liquid in the graduated cylinder is salt water, and the top half water, what conclusions can you make with respect to the density of the egg. Foe example, is the egg denser than salt water? than pure water? Why? 2. A 325gram piece of gold at 425C is dropped into 200ml of water at 22.0C. The specif

### electron is projected to a fixed proton

An electron is projected with an initial speed of 4.8 *10^5 m/s directly toward a proton that is fixed in place. If the electron is initially a great distance from the proton, at what distance from the proton is the speed of the electron instantaneously equal to twice the initial value?

### Mechanics: Motion of a Ball Rolled on Incline and Projectile

A small steel ball is rolled down an inclined plane from a table. The inclined plane is a slotted ruler. One end of the ruler is 10cm off of the table. The ball leaves the table horizontally and lands 46cm from the table on the floor. The table is 72 cm from the ground. 1. Using projectile motion equations, determine the spee

### Spring Compression with Moving Blocks

A block of mass slides along a frictionless table with a speed of 10 m/s. Directly in front of it, and moving in the same direction, is a block of mass moving at 3.0m/s. A massless spring with spring constant is attached to the near side of (the side facing ). When the blocks collide, what is the maximum compression of th

### Simple Harmonic Motion Physical Pendulum, simple pendulum

A file is attached for the sample a mass of 0.5 kg is suspened from a spring, which stretches by 8 cm. the support from which the spring is suspended is set into siusoidal motion. with what frequency should the tip be tapped to make the strip oscillate with the maximum amplitude?

### Simple Harmonic Motion Physical Pendulum, simple pendulum

A file is attached for the sample a mass of 0.5 kg is suspened from a spring, which stretches by 8 cm. the support from which the spring is suspended is set into siusoidal motion. with what frequency should the tip be tapped to make the strip oscillate with the maximum amplitude?

### Conservation of energy problems involving moving particles and systems

(See attached file for full problem description) 19. The graphs attached show the force acting on a particle as the particle moves along the positive x axis from the origin to x = x1. The force is parallel to the x axis and is conservative. The maximum magnitude F1 has the same value for all graphs. Rank the situations accor

### Conservation of energy questions: skier and a particle in a bowl

39) A particle of mass m=30 g slides inside a bowl whose cross section has circular arcs at each side and a flat horizontal central portion between points a and b of length 20 cm. The curved side oft he bowl are frictionless, and for the flat bottom the coefficient of kinetic friction Mk-0.21. The particle is released from rest

### Mechanics: Force, energy and momentum.

1. A 0.25 kg ball is thrown straight up into the air with an initial speed of 19 m/s. Find the momentum of the ball at the following locations. (a) at its maximum height (b) halfway to its maximum height 2. A 2.75 kg steel ball strikes a wall with a speed of 10.0 m/s at an angle of 60.0Â° with the surface. It bounces off

### Force and Distance: Physics Problems

1. A 5.3 g bullet leaves the muzzle of a rifle with a speed of 336 m/s. What force (assumed constant) is exerted on the bullet while it is traveling down the 0.92 m long barrel of the rifle? 2. A shopper in a supermarket pushes a loaded cart with a horizontal force of 12 N. The cart has a mass of 29 kg. (a) How far will i

### Number of collisions in a nuclear reactor

Examine the effectiveness of graphite as a moderator in the nuclear reactors by calculating how much energy a 2 MeV neutron loses in a head on collision with a 12C nucleus. Extend this calculation to find out how many such collisions are required to reduce the neutron kinetic energy to 0.025 eV.

### Elastic Collision in Reactors

A neutron in a reactor makes an elastic head-on collision with the nucleus of a carbon atom initially at rest. (a) What fraction of the neutron's kinetic energy is transferred to the carbon nucleus? (b) If the initial kinetic energy of the neutron is 1MeV = 1.6*10^(-13)J, find its final kinetic energy and the kinetic energ

### Series and Parallel

1.) A box has three identical bulbs mounted on its top with the wires hidden inside the box. Initially bulb A is the brightest and bulbs B and C are equally bright. If you unscrew A, bulbs B and C go out. If you unscrew B, A gets dimmer and C gets brighter so that A and C are equally bright. If you unscrew C, A gets dimmer a

### Momentum and collisions

1) A 10.0 g moving to the right at 20.0 cm/s makes and elastic head on collision with a 15.0 g object moving in the opposite direction at 30.0 cm/s. Find the velocity of each object after collision. 2) a 90 kg fullback moving east with a speed of 5 m/s is tackled by a 95 kg opponent running north at 3.0 m/s. If the collis

### Coefficient of Restitution of a superball

The coefficient of restitution, e, for a ball hitting a stationary surface with a velocity v1 and rebounding with a velocity v2 is: e = - v2/v1 The value of e is positive, because v1 and v2 have opposite directions, and can be any number from 0 to 1 for a passive collision with the surface(no explosive type energy release