Assertion Force constant, k=(Y A/l), where Y is Young's modulus, A is area and l is original length of the given spring. Reason Force constant in case of a given spring is called spring constant.

Question

Assertion Force constant, k=(Y A/l), where Y is Young's modulus, A is area and l is original length of the given spring. Reason Force constant in case of a given spring is called spring constant. (A) If both Assertion and Reason are true and the Reason is correct explanation of the Assertion (B) If both Assertion and Reason are true but Reason is not correct explanation of the Assertion (C) If Assertion is true but Reason is false (D) If Assertion is false but the Reason is true

Tardigrade Admin · Accepted Answer

Here, both Assertion and Reason are true but Reason is not the correct explanation of Assertion. As, Y=(F/A) (l/Δ l) or (F/Δ l)=(Y A/l)=k (as F=K ⋅ Δ l )

Q. Assertion Force constant, $k = \frac{Y A}{l}$ , where $Y$ is Young's modulus, $A$ is area and $l$ is original length of the given spring.
Reason Force constant in case of a given spring is called spring constant.

If both Assertion and Reason are true and the Reason is correct explanation of the Assertion

If both Assertion and Reason are true but Reason is not correct explanation of the Assertion

If Assertion is true but Reason is false

If Assertion is false but the Reason is true

Here, both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
As, $Y = \frac{F}{A} \frac{l}{Δ l}$
or $\frac{F}{Δ l} = \frac{Y A}{l} = k$ (as $F = K \cdot Δ l$ )

Q. Assertion Force constant, k=lYA​, where Y is Young's modulus, A is area and l is original length of the given spring. Reason Force constant in case of a given spring is called spring constant.