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Physics - Gravity

An astronaut weighs 134N while she is training on the moon. On the moon, g=1.61nkg^-1
Calculate her mass...

Now I thought that is g=f/m
Then m = fg but my answer is wrong. Could somebody please explain. The answer says 83.2kg


Posted from TSR Mobile
Reply 1
Mass=weight/gravitational field strength
So it's 134/1.61 :smile:

You basically need to rearrange the equation weight=mass*gravitational field strength.
(edited 11 years ago)
Original post by Pilot96
An astronaut weighs 134N while she is training on the moon. On the moon, g=1.61nkg^-1
Calculate her mass...

Now I thought that is g=f/m
Then m = fg but my answer is wrong. Could somebody please explain. The answer says 83.2kg


Posted from TSR Mobile


You've just rearranged the formula wrong:

F=ma
Therefore for gravity,
F=mg
So,
m=F/g

:top:

Posted from TSR Mobile
Reply 3
Well... Start with standard equations and build up.

F=ma (but we know the acceleration there is 1.61, or just "g")
F=mg
To find the mass, we need to get rid of "g" from the right hand side. To do that, divide through by "g"
F/g = m

Substitute the values.

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