Question

A 75 kg man stands on a spring scale in an elevator. Starting from rest, the elevator ascends, attaining its maximum speed of 1.9 m/s in 0.82 s. It travels with this constant speed for the next 5.9 s, undergoes a uniform negative acceleration for 1.42 s, and comes to rest. Scale What does the spring scale register before the elevator starts to move? The acceleration of gravity is 9.8 m/s 2 . Answer in units of N.

Answer 1

735N

Step-by-step explanation:

Before the elevator starts to move the external force exerted to the man is the gravitational force, so:

`F_g=m*g`

the man's mass is 75kg and the acceleration of gravity 9.8m/s²

`F_g=75kg*9.8m/s^2\\F_g=735N`

the scale registers 735N