Question

Assertion :Upthrust on a solid block of iron when immersed in a lake will be less on the surface than on the bed of the lake. Reason: On the surface of the lake density of water will be less than that at the bed and upthrust depends on the density of liquid.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is A Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

If we can approximate the lake as an ideal gas,

$PM=\rho RT$

Now, at the bottom of the lake, the pressure is more. As a result, the density will also be more for all other parameters held constant.

Therefore, the reason is correct and it explains the assertion correctly