Question

an object of mass m is hanging by a string from the roof of an elevator. the elevator is moving up at a constant speed. what is the tension in the string? multiple choice equal to mg depends on the speed of the elevator less than mg greater than mg

Explanation:

When the elevator moves at constant speed, acceleration \( a = 0 \). By Newton’s second law (\( F_{net}=ma \)), net force on the object is 0. The forces on the object are tension \( T \) (upward) and weight \( mg \) (downward). So \( T - mg = 0 \), hence \( T = mg \).

Answer:

A. equal to \( mg \)