Question

A particle moves on a straight line with a uniform velocity. The angular momentum of the particle is:

• A. Always zero
• B. Zero about a point on the straight line
• C. Zero about a point away from the straight line.
• D. None of the above

Answer 1

Answer: (B)

Zero about a point on the straight line

As$L=mvr$ therefore $L=0$, when $r=0$ i.e. when point lies on the straight line. When a given point does not lie on the line, $r=consatnt$.

Therefore,$L=mvr=consatnt$.