Question

A physics student swings a pail of water in a vertical circle 1.0 m in radius at a constant speed. If the water is NOT to spill on him/her: (A) calculate the minimum speed of the pail of water (B) calculate the maximum time per revolution (period) of the swing

Answer 1

(A) 3.1 m/s

(B) 2.0 s

Step-by-step explanation:

At the minimum speed, the force of gravity equals the centripetal force.

mg = m v² / r

v = √(gr)

v = √(9.8 m/s² × 1.0 m)

v = 3.1 m/s

The time is the circumference divided by the speed.

t = (2π × 1.0 m) / (3.1 m/s)

t = 2.0 s