A ball is thrown with a velocity 2m/s (relative to ground) on a belt which is moving with velocity 4m/s in the oppposite direction. If the block stops slipping after 4seconds , what is displacement of ball in 4 seconds with respect to the belt?

Question

souvik · Answer

@theEric 
difficult one..

theeric · Answer

This is tricky, I'm not sure why yet. Is the "block" the ball?

souvik · Answer

that 'block'.....??!! i did not understand yet...it should be ball...
okay lets solve it together...@theEric

theeric · Answer

Haha, sounds good. We seem to make a good team! So, are we going to say it's just a ball, the whole time? I'd prefer block the whole time, haha,  but @bolan_abhi isn't around to tell us.

There is no mention of kinetic friction, but it says, "slipping."

theeric · Answer

But it stops slipping after four seconds, meaning static friction took effect there.

If this is a ball, it would roll, wouldn't it?

souvik · Answer

after 4 sec it would roll perfectly...

theeric · Answer

The friction force would cause it to spin... I can't really comprehend all the principles taking place in this one.

The friction force causes a change in the angular momentum. The ball would be assumed a sphere..

While the ball slid, it still rotated, but not at the speed of the belt (like it would after four seconds).

theeric · Answer

I don't know how the balls linear momentum would be affected, making this problem very difficult.

amistre64 · Answer

i read it as:  the belt stops moving after 4 seconds

amistre64 · Answer

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