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A 8.2 kg thin hollow spherical shell is rotating about an axis through its center. If the shell is spinning with an angular frequency of 14.0 rad/s, and if it has 8.1 J of rotational kinetic energy, what is its radius (in m)?

At 15 minutes past the hour, a 65.0 g mouse runs up a grandfather clock and sits himself down at the end of the minute-hand. If the minute-hand for the clock is 16.0 cm long, what is the magnitude of the torque exerted by the mouse on the minute-hand? Give your answer in the standard units of N m.

A 2.9 m bar with negligible mass is fastened such that it hangs straight out from the side of a building. A cable is attached to the end of the metal bar on one end, with the other end attached to the building wall above the bar. The angle between the cable and the bar is 20.1 degrees (marked as theta in the image). If a 6.0 kg mass is hung from the bar at a distance of 2.1 m from the wall, what is the force of tension (in N) in the cable?

Hint: You will have to determine the two torques on the bar such that the system is in equilibrium. Set your pivot as the point where the bar is connected to the building. You should have one positive and one negative torque acting against one another.

A barbell with two equal masses 2.7 kg on either end rotates about an axis perpendicular to the bar with an angular velocity of 2.62 rad/s. If one of the masses is 0.28 m away from the axis of rotation and the entire system has a rotational kinetic energy of 19.2 J, how far away is the other mass from that axis (in meters)?

Note: Treat the weights on the barbell as point masses, so that you can use I = mr2.

Assume you are given two objects whose centre of mass is located exactly at the origin. The first object has a mass of 38.0 kg and is located at position +26.0 m with respect to the origin. If the mass of the second object is 7.9 kg, what is its position (in m) with respect to the origin?

Lin is firmly attached to a snowboard which is on a flat surface of ice, which you can assume to be frictionless. She and the snowboard are initially at rest. She then throws a 138.0 g ball which travels at a speed of 15.2 m/s, and finds herself moving backwards at a speed of 0.09 m/s. What is the combined mass of Lin and her snowboard (in kg)?

Joe has an average useful power output of 46.6 W. What would be the minimum time (in ms) it would take Joe to pull a spring with a spring constant of 330.0 N/m a distance 72.0 cm beyond its relaxed position?

A 9.8 kg dog is leaping through the air in order to catch a 538.0 g ball. The horizontal component of the dog's velocity is 4.5 m/s, and the ball, travelling in the same direction as the dog, has a horizontal velocity component of 11.0 m/s. Once the dog catches the ball, what is the horizontal component of the dog's velocity (holding the ball) in m/s.

Hint: This is a completely inelastic collision. Also, you do not have to deal with gravity in this question as it deals strictly with motion in 1D. The question would be the same if the dog were to be moving on flat, frictionless ice, though not as realistic.

A bowling ball is floating motionless in a vacuum just minding its own business. Suddenly it explodes into two pieces. The instant after the explosion, one piece has a mass of 521.0 g and flies off to the right at 1.55 m/s. The remaining piece flies off to the left at 1.31 m/s. Using this information, figure out what the mass of the bowling ball was before the explosion. Note that the motion remains in one dimension the whole time! Also, be sure to give your answer in grams.

Light travelling in one material enters another material in which it travels faster. The light wave will:

Question options:

A) increase in frequency

B) increase in wavelength

C) decrease in frequency

D) decrease in wavelength

E) travel through the new material inverted

If point charge - q was absent, the electric field at point B would be E. What is the electric field between the two point charges, -q and -q, at point B which lies at the midpoint between he two charges?

Diagram: http://i.imgur.com/1ESjTz1.png

The moon's period of revolution around the Earth is 27.3 d. How far away is the moon?

Two mountains are 1.00 km apart. If their masses are identical (2.00 × 1010 kg), what is the force due to gravity between the mountains?

Two objects are experiencing a force of gravitational attraction. If you triple the mass of one of the objects and double the distance between their centers, the new force of gravity compared to the old (Fg) will be:

During a free dance program in figure skating, Victor (m = 71 kg) glides at 2.1 m/s to a stationary Shae-Lynn (52 kg) and hangs on. How far will the pair slide after the “collision” if coefficient of kinetic friction µk between their skates and the ice is 0.052?

A frictionless disc of mass 0.50 kg is moving in a straight line across an air table at a speed of 2.4 m/s when it bumps into an elastic band stretched between two fixed posts. If the elastic band exerts an average opposing force of 1.4 N on the disc for 1.5 s, what will be the final velocity of the disc?

Two objects of mass 7.2 kg and 6.9 kg collide head-on in a perfectly inelastic collision. If the initial velocities of the objects are respectively 3.6 m/s [N] and 13 m/s [S], what is the velocity of both objects after the collision?

An arrow of mass 0.08 kg travelling at 25 m/s [forward] pierces an apple of mass 0.2 kg that was travelling at 5 m/s in the same direction. what is the velocity of the combined arrow/apple immediately after the strike?

Two carts having masses 2.3 kg and 2.7 kg are on a frictionless track. The lighter cart travelling at 5.0 m/s collides with the heavier stationary cart. The two carts latch together and continue rolling down the track. The velocity of the carts is now ...?

Two carts each with mass 1.2 kg are on a frictionless track. The first cart travelling at 3.0 m/s collides with the second stationary cart. The two carts latch together and continue rolling down the track. The velocity of the carts is now...?