Two particles $A$ and $B$ are moving as shown in the figure. Their total angular momentum about the point $O$ is
- 9.8 kg $m^2/s$
- Zero
- 52.7 kg $m^2/s$
- 37.9 kg $m^2/s$
The Correct Option is A
Solution and Explanation
$L = L _{1}+ L _{2}=m_{1} v_{1} r_{1}+m_{2} v_{2} r_{2}$
$=-6.5 \times 2.2 \times 1.5+3.1 \times 3.6 \times 2.8$
$=-21.45+31.248=9.8\, kgm ^{2} / s$
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Concepts Used:
System of Particles and Rotational Motion
- The system of particles refers to the extended body which is considered a rigid body most of the time for simple or easy understanding. A rigid body is a body with a perfectly definite and unchangeable shape.
- The distance between the pair of particles in such a body does not replace or alter. Rotational motion can be described as the motion of a rigid body originates in such a manner that all of its particles move in a circle about an axis with a common angular velocity.
- The few common examples of rotational motion are the motion of the blade of a windmill and periodic motion.