A passenger of mass 72.2kg is riding in an elevator while standin… - Vidyadip

Question

A passenger of mass 72.2kg is riding in an elevator while standing on a platform scale. What does the scale read when the elevator cab is:

Descending with constant velocity,
Ascending with constant acceleration, 3.5m/ s?

✓

Answer

Given, mass, m = 72.2kg

Gravity acceleration, g = 9.8m/ s²

Scale reading = apparent weight = R = ?

While descending with constant velocity, a = 0

R = mg

R = 72.2 × 9.8

R = 707.56N

While ascending with a = 3.2m/ s

R = m(g + a)

R = 72.2(9.8 + 3.2) = 938.6N

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