Question

A) What will a spring scale read for the weight of a 54-kg woman in an elevator that moves upward with constant speed 5.0 m/s?

B) What will a spring scale read for the weight of a 54-kg woman in an elevator that moves downward with constant speed 5.0 m/s?

C) What will a spring scale read for the weight of a 54-kg woman in an elevator that moves upward with acceleration 0.35g?

D) What will a spring scale read for the weight of a 54-kg woman in an elevator that moves downward with acceleration 0.35 g ?

E) What will a spring scale read for the weight of a 54-kg woman in an elevator that moves in free fall?

Answer 1

Here , for the readings of the scale

A) m = 54 Kg

for the reading of the scale

reading of scale = m * (g + a)

for constant velocity , a = 0

reading of scale = 54 * (9.8) = 529.2 N

the reading of scale is 529.2 N

B) m = 54 Kg

for the reading of the scale

reading of scale = m * (g + a)

for constant velocity , a = 0

reading of scale = 54 * (9.8) = 529.2 N

the reading of scale is 529.2 N

C) m = 54 Kg

for the reading of the scale

reading of scale = m * (g + a)

for constant velocity , a = 0.35g

reading of scale = 54 * (9.8 + 0.35 * 9.8) = 714 N

the reading of scale is 714 N

D)
m = 54 Kg

for the reading of the scale

reading of scale = m * (g + a)

for constant velocity , a = -0.35g

reading of scale = 54 * (9.8 - 0.35 * 9.8) = 344 N

the reading of scale is 344 N

E)

m = 54 Kg

for the reading of the scale

reading of scale = m * (g + a)

for constant velocity , a = g

reading of scale = 54 * (9.8 - 9.8) = 0 N

the reading of scale is 0 N