NEET Physics Question - Circular Motion

Assertion (A): Two identical trains move in opposite sense in equatorial plane with equal speed relative to earth's surface. They have equal magnitude of normal reaction.

Reason (R): The trains require same centripetal force although they have different speeds.

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

Solution:

The absolute speed of the trains relative to Earth's center is \( v_{\text{abs}} = R_E \omega_E pm v_{\text{surface}} \). Since their absolute speeds are different, the centripetal force required \( F_c = m v_{\text{abs}}^2 / R_E \) will be different. The normal reaction is \( N = mg - F_c \), so it will also be different. Therefore, both Assertion (A) and Reason (R) are false.

Rankers Physics

Assertion and Reason: Trains on Equator

Solution:

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