Question

Assertion: mN and Nm represent SI units of the same physical quantity.

Reason: They represent different physical quantities as:

1 mN = 10⁻³ N

1 Nm is the SI unit of moment of force.

Options

• 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 the Reason is false.

• If Assertion is false, but the Reason is true.

Answer 1

If Assertion is false, but the Reason is true.

Explanation:

mN and Nm do not represent the same physical quantity. mN means millinewton, which is a unit of force, while Nm is the SI unit of moment of force or torque. Therefore, the Assertion (A) is false.

1 mN = 10⁻³ N

and 1 Nm represents the unit of moment of force. Therefore, the Reason (R) is true.

Hence, A is false but R is true.