JEE Mains · Physics · STD 11 - 7. gravitation

Given below are two statements: One is labelled as Assertion \(A\) and the other is labelled as Reason \(R\). Assertion \(A\): If we move from poles to equator, the direction of acceleration due to gravity of earth always points towards the center of earth without any variation in its magnitude. Reason \(R \): At equator, the direction of acceleration due to the gravity is towards the center of earth. In the light of above statements, choose the correct answer from the options given below

A Both \(A\) and \(R\) are true and \(R\) is the correct explanation of \(A\).
B Both \(A\) and \(R\) are true but \(R\) is NOT the correct explanation of \(A\).
C \(A\) is true but \(R\) is false
D \(A\) is false but \(R\) is true

Verified Solution

Answer & Solution

Correct Answer

(D) \(A\) is false but \(R\) is true

Step-by-step Solution

Detailed explanation

Effective acceleration due to gravity is the resultant of \(g\) and \(rw ^{2}\) whose direction and magnitude depends upon \(\theta\). Hence assertion is false. When \(\theta=0^{\circ}\) (at equator), effective acceleration is radially inward.

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.

Same subject

Explore more questions on app

From JEE Mains

Explore more questions on app