How Does Acceleration Affect Weight Measurements on a Scale?

AI Thread Summary
When a 60kg pupil is accelerated upwards at 3m/s², the reading on a bathroom scale can be calculated using the formula F=m(g-a). The weight of the pupil is 600N, and the additional force due to acceleration is 180N, resulting in a total force of 780N. This total force corresponds to a weight measurement of 78kg on the scale. The discussion highlights the relationship between the normal force, weight, and the effects of acceleration on scale readings. Understanding these principles is crucial for accurately interpreting weight measurements under varying conditions.
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Homework Statement



the question given is:

What would the reading on a bathroom scale be if a 60kg pupil was accelerated upwards at a rate of 3m.s-2


Homework Equations



F=m(g-a)
F=ma

The Attempt at a Solution




F=m(g-a)
F=60kg(10m.s-2-3m.s-2)
F=600-180
F=420N which is equal to the force on the person
The reading on the scale is therefore (42kg + 60kg) or 102kg but this seems too high

Thanks for helping :wink:
 
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The resultant force,F is upwards. The forces acting are the normal reaction upwards,R, and the weight W. Can you make a simple relationship between F,W and R?
 
Thanks for the help rock but i figured it out just before i saw your post.

F=ma

F=60x3
F=180N
=extra force added to weight

therefore the total value showed on the scale is
W= 180N + 600N (the mass converted to weight)
W= 780N
M= 78kg

Thanks again for the help
 

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