What Does the Scale Read When the Elevator Moves Downward?

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SUMMARY

When Harold, with a mass of 72.2 kg, stands on a scale in an elevator moving downward at a constant velocity of 0.050 m/s, the scale reads his weight without any additional forces acting on him. Since the elevator's velocity is constant, the acceleration is zero, meaning the normal force exerted by the scale equals Harold's weight. The calculation for his weight is W = mg, resulting in W = 72.2 kg * 9.8 m/s² = 708 N. Therefore, the scale will read 708 N.

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  • Understanding of Newton's laws of motion
  • Knowledge of free body diagrams
  • Familiarity with the concept of normal force
  • Basic grasp of weight calculation using W = mg
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Homework Statement



Harold has a mass of 72.2 kg, and is standing on a scale in an elevator cab. What will the scale read if the elevator is moving downwards at a constant 0.050 m/s?

Homework Equations


The Attempt at a Solution



Since the scale has a normal force upward and Harold has an identical normal force downward (assuming this is correct). Well that means that the only thing affecting the scales weight is the mass * acceleration correct?

A free body diagram showed ma downward and I'm not sure if I was suppose to draw anything else (I drew the normal force but wasn't sure if it was equal to anything)

In a separate attempt the weight = mg

so W = 72.2 * 9.8 = 708N

*EDIT = I didn't realize that the acceleration is 0 since velocity is constant until now
 
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Nirupt said:

Homework Statement



Harold has a mass of 72.2 kg, and is standing on a scale in an elevator cab. What will the scale read if the elevator is moving downwards at a constant 0.050 m/s?


Homework Equations





The Attempt at a Solution



Since the scale has a normal force upward and Harold has an identical normal force downward (assuming this is correct). Well that means that the only thing affecting the scales weight is the mass * acceleration correct?

A free body diagram showed ma downward and I'm not sure if I was suppose to draw anything else (I drew the normal force but wasn't sure if it was equal to anything)

In a separate attempt the weight = mg

so W = 72.2 * 9.8 = 708N


*EDIT = I didn't realize that the acceleration is 0 since velocity is constant until now
Does this mean you have found your answer?
 

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