Question

An object is hanging by a string from the ceiling of an elevator. The elevator is moving upward with a constant speed. What is the magnitude of the tension in the string?

Answer 1

Equal to the weight of the object

Step-by-step explanation:

There are two forces acting on the object hanging on the string:

- The tension in the string, T, acting upward

- The weight of the object, mg, acting downward

We can write Newton's second law as:

`T-mg=ma`

where a is the acceleration of the object.

Here we are told that the elevator is moving at constant speed: this means that the acceleration of the object is zero, therefore a = 0 and the equation becomes

`T=mg`

therefore, the tension in the string is equal to the weight of the object.