Question

A person who weighs 800 n steps onto a scale that is on the floor of an elevator car. If the elevator accelerates upward at a rate of 5 m/s2, what will the scale read?

Answer 1

mass = weight / g

m = 800/9.8

= 81.63 kg

Total acceleration = 9.8 + 5 = 14.8 m/s^2

F = ma, where a = 14.8

= (81.63)(14.8)

= 1208 N  ANS

Answer 2

Dear Student,

● Answer -

W' = 1208 N = 123.28 kg wt

● Explaination -

# Given -

W = 800 N

a = 5 m/s^2

# Solution -

Mass of the man is calculated as -

m = W / g

m = 800 / 9.8

m = 81.63 kg

When the man is standing in elevator accelerating upwards, effective acceleration acting on him is -

a' = a + g

a' = 5 + 9.8

a' = 14.8 m/s^2

So scale reading of weight of the man is -

W' = m × a'

W' = 81.63 × 14.8

W' = 1208 N

W' = 123.28 kg wt

Hence, his weight on scale is 1208 N.

Hope this helps you...