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redshift
Jun9-04, 07:18 AM
"In an elevator that is moving with constant acceleration, a person of 50 kg mass is standing on a bathroom scale that shows "55 kg". Determine the accerlation of the elevator."
I'm pretty sure my answer is right. I'm just wondering if there's another way.

So, 55 kg is 1.1 times 50 kg.
Therefore, the normal force (Fn) acting on the person is 1.1mg

By Newton's second law,
F = ma
Fn - mg = ma
a = (Fn -mg)/m
a = (1.1mg - mg)/m (plugging in the above substitution)
a = g(1.1-1)
a = 0.98 m/s^2

arildno
Jun9-04, 08:34 AM
There are possibly many ways (I don't know any, though) to solve this problem correctly, but your way seems to me as the simplest, and hence, most elegant.