Asked by: Anonymous
A teddy on the inside of a spinning drum is in motion and therefore has velocity.
Newton’s laws of motion predict that this movement would make the teddy want to travel forward forever in a straight line unless acted on by another force. Here, the drum exerts that other force, as it overcomes the tendency for the bear to move forward. This is the centripetal force and the teddy feels it pushing it towards the centre of the washing machine.
But, as the teddy is stationary with respect to the surface of the spinning drum, its body exerts an equal and opposite force outwards. This is the fictitious sensation that is often described as centrifugal force.
In short then, on a sufficiently fast spin cycle, centripetal force would hold the bear against the drum, even if the washing machine was in space.
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