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41 votes
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If the tidal bulge on the earth speeds the moon up, how does the moon move to a higher orbit?

To understand this, let’s start with a simpler example of orbital mechanics. Suppose we have a rocket in a circular orbit that wishes to transfer to a higher circular orbit. This proceeds in the ...
Dale's user avatar
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1 vote

Direction of the normal force

When the bar is about to tip over, it is impossible for the normal force to act in the direction of the bar. Since the final situation is not very clearly specified, I will take 2 cases. The rod left ...
Dev Not Taken's user avatar
1 vote

Proof of Newton's second law of rotation for rigid body

Use the equation for a single particle and apply summation over all of them. Then use newton's third law to cancell out internal forces.
mathemaster's user avatar
1 vote
Accepted

Proof of Newton's second law of rotation for rigid body

For a particle in the rigid body we have $$\tau = \frac{dL}{dt}$$ And $\mathbf{\tau} =\mathbf{ r\times F}$ This gives us $$\frac{dL_i}{dt}=\mathbf{ r_{i}\times F_{net,i}}$$ Where $$F_{net,i}$$ is the ...
Aarush Saharan's user avatar
1 vote

What is the formula for how a force affects linear motion on a rigid body?

When it comes to dynamics human intuition is often wrong. What is important is the mathematical modeling and the story it tells you in each situation. Consider the following points Newton's 2nd law ...
John Alexiou's user avatar

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