Centre of Mass in Pure Rolling – Rankers Physics

Calculation of Center of Mass: Practice Problem & Solution

Assertion (A): Centre of mass of a body in pure rolling on a horizontal surface always moves in a straight line. Reason (R): Centre of mass of a body must be inside the body.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Short Solution (Best for NEET):

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

Assertion (A) is true; the center of mass of a body in pure rolling on a horizontal surface moves along a straight line (rectilinear motion). Reason (R) is false; the center of mass can be outside the physical boundaries of the body (e.g., for a ring or a hollow sphere).

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