Posted by **james** on Wednesday, July 25, 2012 at 6:33pm.

A shoe case weighing 40 lb is located on a scale inside a moving elevator that is going upward with the speed of 8 m/s. At time T1 elevator slows down with the acceleration of 3 m/s2 until the time T2. What are the the readings of the scale at T2 and T1 respectively?

- science -
**drwls**, Wednesday, July 25, 2012 at 7:54pm
While the upward velocity is decreasing, there is downward acceleration at rate a = 3 m/s^2

At time T1, the scale reads force F.

W - F = M a

F = W - M a = W - (W/g) a

= W (1 - a/g) = 40 lb * (6.8/9.8)

If acceleration = 0 at T2, the scale reads 40 lb then. We are able to use metric units for a and g because We are calculating a ratio.

## Answer this Question

## Related Questions

- physics - A 80-kg man stands on a bathroom scale inside an elevator. (a) The ...
- dynamics of rigid bodies - 1. An elevator weighing 15 kN starts from rest and ...
- Physics - A 44.0 kg man stands on a bathroom scale in an elevator. Starting from...
- physics - Apparent Weight. A physics student weighing 600 N stands on a bathroom...
- Physics - A 46.0 kg man stands on a spring scale in an elevator. Starting from ...
- Physics - Riding in an elevator, a man notices that he feel heavier or lighter ...
- physics - A 70kg man stands on a bathroom scale in an elevator. As the elevator ...
- Help Physics - A child with a mass of 39 kg stands on a spring scale inside an ...
- Physics - A man measures the acceleration of an elevator using a spring balance...
- Physics - A man measures the acceleration of an elevator using a spring balance...

More Related Questions