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Energy

Frequency of Motion

Solid, uniform cylinder of mass m and radius R is fitted with a frictionless axle along the cylinder's long axis. A horizontal spring (spring constant k) is attached to this axle. Under the influence of the spring, the cylinder rolls back and forth without slipping on a horizontal surface. What is the frequency of this motion?

Pulley Setup and Kinetic Energy

A m1 = 49.0 kg block and an m2 = 103.0 kg block are connected by a string as in Figure P7.28. The pulley is frictionless and of negligible mass. The coefficient of kinetic friction between the 49.0 kg block and incline is 0.250. Determine the change in the kinetic energy of the 49.0 kg block as it moves from A to B, a distance o

Solving for Height

An 11 kg bowling ball is dropped into a tub containing a mixture of ice and water. A short time later, when a new equilibrium has been established, there are 5.0 g less ice. From what height was the ball dropped? Part A Assume the bowling ball has an initial temperature of 0 degreesC, and that no water or ice splashes out.

Block Problems

1) A stationary block explodes into two pieces that slide along a frictionless floor and then into regions with friction, where they stop. The first piece, with a mass of 2.0 kg, encounters a coefficient of kinetic friction of 0.40 and slides to a stop in a distance 0.15 m. The second piece encounters a coefficient of kinetic fr

Photons of energy impinging upon helium ions

Photons of energy 65.561eV and 52.324eV impinge upon a collection of helium ions (He* , Z = 2). a. Can the photons of energy 65.561eV be absorbed by the helium ions without ejecting the electron from the ions if the electron is initially in the ground state? If so, to which state is the electron promoted? If not, why not?

Momentum and Collisions on a Frictionless Surface

Please help me with this question: On a frictionless horizontal air table, puck A (with mass .250 kg) is moving toward puck B (with mass .350 kg), which is initially at rest. After the collision, puck A has a velocity of .120 m/s to the left, and puck B has velocity .650 m/s to the right. a) What was the speed of puck A b

Rotational Motion: Rod released on smooth horizontal plane

A thin rod of length h and mass M is held vertically with its lower end resting on a frictionless horizontal surface. The rod is then released to fall freely. Determine the speed of its center of mass just before it hits the horizontal surface. Use h, M, and g for length, mass, and gravitational acceleration respectively. (b)

3 Physics Problems

(See attached files for full problem description with units and diagrams) --- A package of mass is released from rest at a warehouse loading dock and slides down a 3.0-m-high frictionless chute to a waiting truck. Unfortunately, the truck driver went on a break without having removed the previous package, of mass 2 , from

Motion in a vertical circle: conservation of energy

A pendulum consists of a string of length L and a bob of mass M. The string is brought to a horizontal position and given the minimum initial speed enabling a pendulum to make a full turn in the vertical plane. a) what is the maximum kinetic energy K of the bob? b) what is the tension in the string when the kinetic energy is

Find compression of spring at bottom of incline

A block of mass m starts from rest at a height h and slides down a frictionless plane inclined at theta with the horizontal. The block strikes a spring of force constant k. Find the compression of the spring when the block is momentarily at rest.

Calculating the Power of a Pump

Question: A pump is required to lift 800 kg of water (about 210 gallons) per minute from a well 14.0m deep and eject it with a speed of 18.0 m/s. a) How much work is done per minute in lifting the water? b) How much in giving the water the kinetic energy it has when ejected? c) What must be the power outpu

Collision in One Dimension

(See attached file for full problem description with diagrams and units) On a frictionless horizontal air table, puck A (with mass 0.369 ) is moving toward puck B (with mass 0.249 ), which is initially at rest. After the collision, puck A has velocity 0.116 to the left, and puck B has velocity 0.645 to the right. a)

Total Kinetic Energy difference to rotational kinetic energy

A thin stick of length L = 1.6 m is denser at one end than at the other: Its mass density is = (0.40 kg/m) - (0.03 kg/m^2)x, where x measures the distance from the heavier end of the stick. The stick rotates with period T = 1 s about an axis perpendicular to the stick through the heavy end. Determine the rotational kinetic ener

CN in molecular clouds

Cold, interstellar, molecular clouds have been seen to contain the cynogen molecule, CN, whose first rotational excited states have an energy of 4.7*10^-4 eV above the ground state. There are actually 3 such excited states, all with the same energy. In 1941, studies of these molecular clouds, using the absorption of starlight pa

A pair of bumper cars in an amusement park ride collide...

A pair of bumper cars in an amusement park ride collide elastically as one approaches the other directly from the rear. (see attachment for diagram) One has a mass of m1 = 464 kg and the other m2 = 560 kg, owing to differences in passenger mass. If the lighter one approaches at v1 = 4.32 m/s and the other is moving at v2 =

Drop height to achieve known deflection in a beam

A .5m long beam with 29N-m stiffness is attached to a 45kg weight. The beam is inclined 30 degrees from vertical. Assume the beam has no mass, assume the 45kg weight is "sliding" down a vertical pole of infinite stiffness and zero friction. The mass is dropped and the end of the beam deflects .095m when it contacts the ground.

Physics problem

A potter's wheel -- a thick stone disk of radius 0.500 m and mass 100 kg -- is freely rotating at 50.0 rev/min. The potter can stop the wheel in 6.00 s by pressing a wet rag against the rim and exerting a radially inward force of 65.0 N. Find the effective coefficient of kinetic friction between the wheel and the rag.

An electron with a speed 5.00x10^8 cm/s enters an electric field of magnitude 1.00x10^3 N/C, traveling along a field line in the direction that retards its motion. (a) how far will the electron travel in the field before stopping momentarily, and (b) how much time will have elapsed? (c) If the region containing the electric field is .08m long, what fraction of the electron's initial kinetic energy will be lost in that region?

An electron with a speed 5.00x10^8 cm/s enters an electric field of magnitude 1.00x10^3 N/C, traveling along a field line in the direction that retards its motion. (a) how far will the electron travel in the field before stopping momentarily, and (b) how much time will have elapsed? (c) If the region containing the electric fiel

Potential and Kinetic energy of an oscillator

A block of mass m = 0.65 kg is fastened to a spring with k = 65 N/m. The block is pulled a distance x = 11 cm from its equilibrium position at x = 0 on a frictionless surface and released from rest at t = 0. v= 1.1 m/s^2 Calculate the potential and kinetic energy of the oscillator when the block is at x = 0.

Potential Difference: Particle Change, Lightning Discharge Etc.

Please show all work and show all equations used and diagrams. 1) If 500J of work are required to carry a 40C charge from one point to another the potential difference between these two points is: 3) The potential difference between two points is 100V. If a particle with a charge of 2C is transported from one of these poi

Understanding the Human Ear

The radius of a typical human eardrum is about 4.0 mm. Find the energy per second received by an eardrum when it listens to sound that is (a) at the threshold of hearing and (b) at the threshold of pain.

Find the kinetic energy

Find the kinetic energy of a cylindrical shaft of mass 2.0 kg and radius 10cm rotating about its central axis at 600 rad/s a. 1800 j b. 1200 j c. 18000 j d. 12000 j

Kinetic energy

A neutron in a nuclear reactor makes an elastic head-on collision with the nucleus of a uranium atom initially at rest. (a) What fraction of the neutron's kinetic energy is transferred to the uranium nucleus? (The mass of the uranium nucleus is about 238 times the mass of the neutron.) (b) If the initial kinetic energy of

Rotational Dynamics

A solid sphere of mass 1.0 kg and radius of .10 m rolls down a 10 m board which makes an angle of 30 degrees to the ground. (a) What will be sphere's speed when it reaches the ground? (b) What will be its rotational speed? (c) What total energy will it have?

Energy and Momentum - Child on a Swing

See the attachment for a diagram of the scenario below. A child with a mass of 22 kg sits on a swing and is held in the position shown by a second child. (35 deg from vertical). Neglecting the mass of the swing, determine the tension in rope AB... a) while the second child holds the swing with his arms outstretched horizont

One dimension collisions

A ball of mass 1.5kg is thrown upward. it leaves the thrower's hand with a velocity of 10 m/s. Assuming the upward direction is positive: a. how long does it take for the ball to return to the throwers hand b.what is the ball's final velocity just before it reaches the hand? c. what is the change in momentum of the ball?