Why does a charged balloon attract small bits of paper, why does this happen? how is it like a magnet attracting paper clips?

The space between two 15-in.-long concentric cylinders is filled with glycerin (viscosity = 8.5 × 10-3 lb·s/ft2). the inner cylinder has a radius of 1 in. and the gap width between cylinders is 0.1 in. determine (a) the torque and (b) the power required to rotate the inner cylinder at 180 rev/min. the outer cylinder is fixed. assume the velocity distribution in the gap to be linear.

Anika asks eva to roll a basketball and then a bowling ball to her. which requires more force to roll, and why?

If it takes 200 joules of energy to lift a bucket of water 3 meters in 2 seconds, how much power would be required to do the same amount of work in 5 seconds?