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Classical mechanics: Motion in two dimension.

1. A river flows due east at 1.00 m/s. A boat crosses the river from the south shore to the north shore by maintaining a constant velocity of 9.0 m/s due north relative to the water. (a) What is the velocity of the boat relative to shore? (b) If the river is 280 m wide, how far downstream has the boat moved by the time it rea

Elastic Collision of Air-Track Glider

An air-track glider with an initial speed of 4.0 m/s has a head-on collision with another glider at rest that is three times as massive. What are the final speed and directions of the gliders if the collision is elastic? I believe the answer is V1 = -2.0 m/s and V2 = +2.0 m/s. I need to see each step and formula to solve this qu

Determining the elasticity of a collision

A steel ball is dropped from a height of 2.37 meters onto a flat stone slab. On rebounding, the sped of the ball is 3.94 m/s when it is 1.52 meters above the stone slab. Is the collision elastic?

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.

Speed of a falling egg

An egg falls from a nest at a height of 3.08 meters. What speed will it have when it is 0.5 meters from the ground? Neglect air friction. 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.

What is the value of the spring constant k?

A 750-gram air-track glider slides along at a speed of 0.85 m/s until it hits a spring attached to the end of the very heavy track. The spring is compressed by 1.35 cm at the maximum compression. What is the value of the spring constant k? I need to see each step and formula to solve this question.

A 0.302-kg coffee mug rests on a table top 0.740 meters above the floor.

A 0.302-kg coffee mug rests on a table top 0.740 meters above the floor. A) What is the potential energy of the mug with respect to the floor? B) What is the potential energy with respect to the counter top 1.100 meters above the floor? I need to see each step and formula to solve this question.

Ratio of Kinetic Energies

Sam can throw a baseball twice as fast as can his little brother, Bill. How many time as much kinetic energy can Sam give the baseball as Bill can?

Energy in the motion of a Ping Pong ball and maximum speed

A 2.5-g Ping-Pong ball at rest is set in motion by the use of 1.8 J of energy. If all of the energy goes into the motion of the ball, what is the balls maximum speed? I believe the answer is 38 m/s. I need to see each step and formula to solve this question.

A full keg of beer is placed at the top of ramp at the back of a pickup truck and released. To find rotational and linear speed of the keg at the bottom of the ramp, kinetic energy of the keg at the bottom of the ramp, time it takes the keg to get to the bottom of the ramp and magnitude of the friction force between the keg and the ramp.

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

1D motion of a quantum particle

Consider the 1D motion of a quantum particle in an external potential with its total energy given by the equation in the attachment. (a) Explain why according to quantum mechanics, the ground state energy (i.e. the lowest possible energy of the particle) can never be zero. (b) By making use of a certain fundamental particl

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

Wavelength and Zeeman Lines

What is the wave length of those three kinds of Zeeman lines emitted when the electron had occurred the transition from 3d(n=3, l=2) to 2p(n=2, l=1) about the hydrogen atom in the magnetic field of 10,000 gauss. *In the 3d(n=3, l=2) to 2p(n=2, l=1), l means lowercase of L.

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)

Momentum & Collisions (rifle bullet)

A rifle bullet with mass 8.00 g strikes and embeds itself in a block with mass 0.992 kg that rests on a friction-less horizontal surface and is attached to a coil spring. The impact compresses the spring 15.0 cm. Calibration of the spring shows that a force of 0.750 N is requires to compress the spring 0.250 cm. 1. Find the

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 stored in capacitor

Consider a parallel plate capacitor with area A and separation d. The plates have fixed charges Q and -Q, and no battery connected. Determine the energy stored before and after the insertion of a dielectric with dielectric constant K that completely fills the space between the plates.

Parallel plate capacitor: Find the energy stored

1. Consider a parallel plate capacitor, fixed area A, and fixed separation, d. Find the energy stored, and after insertion of a slab of dielectric, which completely fills the space between the plates for each of the two cases (a) The plates are connected to a battery which maintains constant potential difference (b) The pl

Free-Falling Bodies - Pellet Gun Question

If a gun is fired straight downward from the edge of a cliff that is 17 m above the ground and the pellet strikes the ground with a speed of 25 m/s. How do you determine how far above the cliff edge that the pellet would have to have gone if the pellet had been fired straight upward

Energy in Thermal Motion

A combination of 0.250 kg of water at 20.0 degrees C, 0.400kg of aluminum at 26.0 degrees C, and 0.100 kg of copper at 100 degrees C is mixed in an insulated container and allowed to come to thermal equilibrium. Neglect any energy transfer to or from the container and determine the final temperature of the mixture.