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Izekid
Oct11-05, 08:19 AM
Pelle who weights 68 kilos, cycles up a steep hill. He stands up and pushes all his weight on the pedals. Pedals moves in a circle with the radie 18cm. Which is the biggest momentum he can affect the pedals with

Well my answer is wrong but this is how I did
Because I don't know the answer I take

m2= 9,82*(0,18)^2 = 0,318168/6,67*10^-11 = 4770134933
Which is the second mass

M1 = His weight 68kg

Then I take 68*4770134933 =3,24691754^10*-11 * 6,67*10^11 = 21,635424
and then I finely dived it which is 21,635424/0,18^2 = 667,76 N

I get but it's not right answer should be 120Nm please help me !:surprised :surprised :surprised :surprised :surprised

Päällikkö
Oct11-05, 08:52 AM
The unit of moment of a force (often called torque) is Nm, and the equation:
\mathbf{M} = \mathbf{r} \times \mathbf{F}

This problem has little to do with gravitation.