A heavy steel ball B is suspended by a cord from a block of wood W.The entire system is dropped through the air.Neglecting air resistance, the tension in the cord is:
A)zero
B)the difference in the masses of B and W
C)the difference in the weights of B and W
D)the weight of B
E)none of these

Question

Quizplus · Accepted Answer

When the entire system is dropped through the air and air resistance is neglected, both the block of wood W and the heavy steel ball B are in free fall. This means they are both accelerating towards the Earth at the same rate due to gravity. Since there is no relative acceleration between B and W, the tension in the cord is zero.

A Heavy Steel Ball B Is Suspended by a Cord