System of Particles and Rotational Motion - Result Question 37
39. A particle of mass $m$ moves in the $X Y$ plane with a velocity $v$ along the straight line $A B$. If the angular momentum of the particle with respect to origin $O$ is $L_A$ when it is at $A$ and $L_B$ when it is at $B$, then
[2007] (a) $L_A=L_B$
(b) the relationship between $L_A$ and $L_B$ depends upon the slope of the line $A B$
(c) $L_A<L_B$
(d) $L_A>L_B$
Show Answer
Answer:
Correct Answer: 39. (a)
Solution:
- (a) Angular momentum = Linear momentum $x$ distance of line of action of linear momentum about the origin.
$L_A=p_A \times d, L_B=p_B \times d$
As linear momenta are $p_A$ and $p_B$ equal,