Kinetic Energy and Linear Momentum of a System – Rankers Physics

Momentum Conservation: Practice Problem & Solution

Assertion: If kinetic energy of a system of particles is zero, then linear momentum of system must be zero. Reason: If linear momentum of a system of particles is zero, then kinetic energy of system must be zero.
Both Assertion and Reason are true and Reason is the correct explanation of Assertion.
Both Assertion and Reason are true but Reason is not correct explanation of Assertion.
Assertion is true but Reason is false.
Assertion and Reason are false.

Solution Explained:

To solve this problem, we apply the core principles of Momentum Conservation. Understanding the underlying formula is key to arriving at the correct answer below:

If the kinetic energy of a system is zero, the speed of each particle must be zero, meaning the total linear momentum is also zero. If the total linear momentum is zero, particles can still be moving in opposite directions, resulting in a non-zero kinetic energy. Thus, the Assertion is true but the Reason is false.

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