Astudent uses a spring to launch a marble vertically in the air . the mass of the marble is 0.002kg and when the spring is stretched 0.05m it exerts a force of 20n. what is the maximum height the marble can reach ?

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.