A particle moves in a circular path with decreasing speed. Choose the correct statement
- Angular momentum remains constant
- Acceleration (a) is towards the centre
- Particle moves in a spiral path with decreasing radius
- The direction of angular momentum remains constant
The Correct Option is D
Solution and Explanation
Direction of $(r \times v),$ hence the direction of angular momentum remains the same.
$\therefore$ Correct answer is (d).
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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.