Spring Scale Readings for MassesSpring Scales Mass Force !

AI Thread Summary
The discussion focuses on two physics questions regarding spring scale readings and lifting forces. For a 500.0g mass, the scale reads 4.9N when stationary, and the reading remains the same when lifted at constant velocity due to the absence of net forces. When released to fall freely, the scale reading drops to zero as the mass is in free fall. Additionally, a student weighing 65kg can safely lift 73% of their mass, which calculates to approximately 47.45kg on Earth. The conversation emphasizes the relationship between mass, weight, and the effects of gravity on spring scales.
mr.mair
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Spring Scales Mass Force !

Homework Statement


This is 2 questions.

1.A student hangs a 500.0g mass on a spring scale. Correct two significant digits, state the reading on the scale when the the mass and the scale are

(a) Stationary
(B) Being Lifted Upward at constant velocity
(c)realesed so they fall downward freely

2. A student 65kg can safetly lift 73% of the students own mass off the floor?
(a) Determine the mass the student can lift on earth

Homework Equations



Fg=mg

The Attempt at a Solution



First Question the stationary I put

Fg= mg
Fg=(0.5)(9.8)
Fg= 4.9N
 
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Question seems to simply be (65kg)(0.73) since mass is independent of gravity or what planet one is on.
 


mr.mair said:
(B) Being Lifted Upward at constant velocity

Well... For part B, if it's moving at a constant velocity (as opposed to a constant acceleration), shouldn't make a difference, right?

I mean, if something is moving at a constant velocity, then that means there are no net forces acting on it. And that would mean that the only force actually acting on the weight and scale would be gravity itself.
 


thanks guys
 
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