A particle of mass `m` is moving along the line `y=b,z=0` with constnat speed `v`. State whether the angular momentum of particle about origin is increasing. Decreasing or constant.

Explanation

`|vecL|= mvr sin theta`
`=" mvr "_bot`
`=" mvb"`

`:." "|vecL|=` constant as m, v and b all are constants. Direction of `vecr xxvecv` also remains the same. Therefore, angular momentum of particle about origin remains constant with due course of time.