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A person who normally weighs 700 N is riding in an elevator that is moving upward but slowing down at a steady rate. If this person is standing on a bathroom scale inside the elevator, what would the scale read?

2 Answers

5 votes

Answer: The answer is less than 700 N

User Eniko
by
6.6k points
3 votes

Answer:

The scale will read less than 700 N

Step-by-step explanation:

Given;

normal weight of the person, W = 700 N

The upward acceleration of the elevator is given by Newton's second law of motion;

F = ma

Also, the weight of the person, W = mg

Net force on the person when the elevator accelerates upward is given as;

R = ma + mg

When the elevator slows down at a steady rate, then net force on the person is given as;

R = mg - ma

R = m(g - a), this net force on the person is also the reading of the scale.

Thus, the scale will read less than 700 N.

User Akio
by
6.2k points