A person weighing 490N stands on a scale in an elevator. What does the scale read (normal force) when the elevator rises at a co
1 answer:
Answer:
490 N
Explanation:
The elevator is rising at constant velocity: this means the acceleration of the system is zero, so according to Newton's second law, the net force on the system is also zero:
There are two forces acting on the person standing on the scale:
- its weight, downward, whose magnitude is W=490 N
- The normal force of the scale on the person, N, which is upward
Since the net force must be zero, we have:
From which we find the normal force:
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