Question

An 800-N woman stands on a scale in an elevator. What does the scale read when the elevator is...

A) ascending at a constant velocity of 3m/s

B) ascending at a constant acceleration of 0.8m/s^2

C) Descending at a constant acceleration of 0.8m/s^2

URGENT!

Answer 1

Answer:

A) 800 N

B) 865.28 N

C) 734.28 N

Explanation:

Given,

The weight of the woman, W = 800 N

Therefore, the mass of the women is

                                m = W/g

                                    = 800/9.8

                                     = 81.53 Kg

A) If the elevator is ascending with a constant velocity, the external acceleration of the body is zero,

Then the elevator readings are

                                        W = mg + ma

                                           = 800 + 0

                                            = 800 N

The elevator reading of the person ascending at constant velocity W = 800 N

B) Ascending at a constant acceleration of 0.8 m/s²

Then the elevator reading are

                                       W = mg + ma

                                            = 800 + (81.65 x 0.8)

                                            = 865.28 N

The elevator reading ascending at constant acceleration is, W = 865.28 N

C) The elevator reading descending at constant acceleration,

                                       W = 800 + (81.65 x 0.8)

                                            = 734.72 N

Hence, the elevator reading descending at constant acceleration is, W = 734.72 N