Zach has a mass of 73 kg and is in an elevator. Initially the elevator is descending at a constant speed of 12 m/s. Zach's apparent weight during this period is equal to the acceleration due to gravity. It is equal to 73*9.8 = 715.4 N

When the elevator starts...

## Unlock

This Answer NowStart your **48-hour free trial** to unlock this answer and thousands more. Enjoy eNotes ad-free and cancel anytime.

Already a member? Log in here.

Zach has a mass of 73 kg and is in an elevator. Initially the elevator is descending at a constant speed of 12 m/s. Zach's apparent weight during this period is equal to the acceleration due to gravity. It is equal to 73*9.8 = 715.4 N

When the elevator starts to brake it comes to a halt in 4 s. The acceleration of the elevator is 12/4 = 3 m/s^2 acting upwards. The net force exerted by Zach on the floor of the elevator is his weight during this period. This gives Zach's weight during this period of 4 seconds as 73*(9.8 + 3) = 934.4 N