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What is the ratio of the masses of the two marbles?

A child playing marbles shoots a marble directly at another marble at rest. The first marble stops, and the second marble continues in a straight line with the same speed that the first marble had initially. What is the ratio of the masses of the two marbles? I need to see each step and formula to solve this question.

A block slides on a semicircular frictionless track.

A block slides on a semicircular frictionless track. If it starts from rest at position (A), what is its speed at the point marked (B)? A picture of the block and slide is attached as a jpeg file. I believe the answer is 3.7 m/s. I need to see each step and formula to solve this question.

Rotational and Linear Speed & Kinetic Energy

A full keg of beer weighs 170 lbf. The beer inside the keg weighs 124lbf and the container weighs 46lbf. The keg is placed at the top of ramp length L=8ft. from the back of your pickup truck to the ground and released. Find: 1. The rotational and linear speed of the keg at the bottom of the ramp. 2. The kinetic engery of th

Illuminance and intensity of light.

1). According to its package, a 100 watt light bulb emits 1140 lumens. For simplicity, assume the bulb provides isotropic illumination and ALL its emission is at 555 nm. A video camera is advertised as having "0.2 lux sensitivity", meaning it can record objects which receive at least this illuminance. In a dark room with no

Particle in a potential well

A particle of mass m moves in the potential V(x) = -g*delta(x) x>-a infinity x<-a (delta (x) = dirac delta function) a. Without worrying about continuity or boundary conditions, write down the general solution of the Schrodinger equation for a bound state (energy E<0) in regions( -a less than x les

Oscillations: The spring with varying force constant

Please see attachment. Thanks. --- Many real springs are more easily stretched than compressed. We can represent this by using different spring constants for and for . As an example, consider a spring that exerts the following restoring force: A mass on a frictionless, horizontal surface is attached to this spring,

Force of Friction and Gravitation Potential Energy

An electric winch pulls a 30.9 kg case of soap up a roller incline 3.01 m high in 3.15 seconds. The case starts from rest at the bottom and is moving 4.02 m/s at the top of the incline. The force of friction on the box is 39.4 N. a) What is the increase in gravitational potential energy of the box? b) Calculate the length

Angular Speed of Rotating Hoop

A string is wrapped several times around the rim of a small hoop with radius r and mass m . The free end of the string is held in place and the hoop is released from rest. Calculate the angular speed of the rotating hoop after it has descended a distance, h. (See attached file for diagram and figures)

Springs and Inclined Planes

1. A light horizontal spring has a force constant of k=100 N/m. A 2.00 kg block is pressed against one end of the spring, compressing it 0.100 m. When the block is released from rest it moves 0.250 m to the right of release position. Show that the coefficient of kinetic friction between the block and the horizontal surface is

DC Circuits: Energy and Current

Assume that the length of an axon membrane of about 10 cm is excited by an action potential (length excited = nerve speed x pulse duration = 50 m/s x 2.0 ms = 10 cm). In the resting state, the outer surface of the axon wall is charged positively with K+ ions and the inner wall has an equal and opposite charge of negative org

Work and Kinetic Energy

The spring of a spring gun has force constant k = 400 N/m and negligible mass. The spring is compressed 6.00 cm and a ball with mass 0.0300 kg is placed in the horizontal barrel against the compressed spring. The spring is then released, and the ball is propelled out the barrel of the gun. The barrel is 6.00 cm long, so the ball

Energy required to create a rabbit "out of thin air".

This figure indicates the energy required to conjure up the rabbit "out of thin-air". Evidently it takes more than energy, U=E, of the rabbit. Please explain, and also tell me why these energies are called "Free". In other words, why did scientists give them such a name? Which figure is correct or are they both correct ?

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?

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

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

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)

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.