Question

An elevator weighing 480 Newtons is supported by a light, vertical cable which exerts a constant force on the elevator, causing the elevator to accelerate upward. Which of the following is the tension, in Newtons, in the cable?
A. Greater than 480
B. Less than 480
C. Equal to 480
D. Data is insufficient to determine the answer
E. 0

Answer 1

Answer:

A. greater than 480

Explanation:

The tension on an object is equal to the mass of the object x gravitational force plus/minus the mass x acceleration.

T = mg +/- ma

T = tension, N, kg-m/s2

m = mass, kg

g = gravitational force, 9.8 m/s2  

a = acceleration, m/s2

since we are accelerating upwards, so it is

T = mg + ma

since it's accelerating upwards, a > 0

therefore 480 + (48a) will always be > 480.

So our answer is A.