One end of a 5.0 m long light string is attached to the ceiling and a small rock of mass m is attached to the other end of the string. The rock swings in a horizontal circle at constant speed. The angle between the string and the vertical direction is a constant 36.9° and the tension in the string is 32.0 N.
a) What is the mass m of the rock?
b) What is the magnitude of the acceleration of the rock as it moves in the horizontal circle?
c) How long does it take the rock to complete one revolution?