Question

A body is projected from ground with some angle to horizontal what happens to the angular momentum about the initial position of motion
Answer : increases
DOUT: why increases angular momentum remains constant

Answer 1

Dear Student...

First let's look at linear momentum along vertical axis. What happens to it? It changes, as it's positive at the beginning, zero at the highest point of trajectory and negative later during the fall. But if we look not only at the thrown body but also at Earth, their total momentum is conserved, as Earth also moves a bit.

​​​​​​ Same with angular momentum: if you only look at the thrown body it seems to be changing from zero at beginning to some non-zero value later during the fall. But if you include Earth too, total angular momentum shall be conserved.

Hope helpful to you...