# Relationship between Rotational & Linear Momentum

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Please imagine you have a chassis (mass M) that is placed on rails (it can move only to one direction i.e axis y). On the chassis centre we have placed a rod that can rotate for half cycle (180 degs) with a high angular velocity and for the rest half cycle it rotates with a very small angular velocity. Also, the starting point for the rotating rod is when it is parallel to the rails (axis y). Due to the rotating rod the chassis will move on the rails. Question is: what is the relationship between the chassis's linear momentum and the rotating rod's angular momentum? Thank you!

The answer lies in Newtons THird law of motion. What is driving the rod rotation? Is it attached to the chassis? If so, Newton's third law is the answer.

The rod is driven by a 2-phased motor and it is attached on the chassis. What do you think is the chassis's velocity when the fast half-rotation is complete? Acccording to action-reaction it should be zero ... but is it?