A person standing on a rotating platform with his hands lowered outstretches his arms. The angular momentum of the persona)becomes zerob)decreasesc)remains constantd)inreasesCorrect answer is option 'C'. Can you explain this answer?

Question

Answer

Explanation: See, when a person outstretches his arms, his moment of inertia increases while angular velocity decreases. As a result the angular momentum of the person remains unchanged. Cheers!

Answer

Angular momentum remains constant till any net external torque is applied on the system.Since here no net torque acts  , only I(Inertial mass) increase so w(angular velocity) decreases to keep the L(=Iw=Angular momentum) constant.

Answer

Angular momentum is a property of a rotating object and is defined as the product of the moment of inertia and the angular velocity. It is a vector quantity and its direction is perpendicular to the plane of rotation. In this scenario, a person is standing on a rotating platform with their hands lowered and then outstretched.

The moment of inertia of the person-platform system remains constant because the mass of the person and the platform does not change, and the distribution of mass remains the same. Therefore, the only variable that can change the angular momentum is the angular velocity.

The angular momentum of the person-platform system is given by the equation L = Iω, where L is the angular momentum, I is the moment of inertia, and ω is the angular velocity.

When the person outstretches their arms, the moment of inertia of the system increases. This is because the mass is distributed farther away from the axis of rotation, resulting in a larger moment of inertia. However, in order to conserve angular momentum, the angular velocity must decrease.

To understand this, consider the law of conservation of angular momentum, which states that the total angular momentum of an isolated system remains constant if no external torques act on it. In this scenario, the person-platform system can be considered an isolated system because no external torques are acting on it.

When the person outstretches their arms, the moment of inertia increases, which means that in order to keep the angular momentum constant, the angular velocity must decrease. This decrease in angular velocity is necessary to compensate for the increase in moment of inertia.

Therefore, the angular momentum of the person on the rotating platform remains constant when they outstretch their arms. The correct answer is option C: the angular momentum remains constant.

Answer

See external torque is zero or constant . so angular mommentum is conserved because you know torque is equal to change in angular momentum.

Answer

As there is no external torque on the system , the angular momentam will remain conserved...

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