In the following questions, a statement of assertion is followed by a statement of reason. Mark the correct choice as
(a) If both assertion and reason are true and reason is the correct explanation of assertion.
(b) If both assertion and reason are true but reason is not the correct explanation of assertion.
(c ) If assertion is true but reason is false.
(d) If assertion and reason are false.
Q. Assertion: Bulk modulus of elasticity B represents incompressibility of the material
Reason: `B=-(triangleP)/((triangleV)/(V))`, where symbols have their usual meaning.

Answer

B

Explanation

Bulk modulus of elasticity measures how good the body is to regain its original volume on being compressed. Therefore, it represents incompressibility of the material.
bulk modulus `B=(triangleP)/((triangleV)/(V))=-((triangleP)V)/(triangleV)`
where `triangleP=`change in pressure
and `triangleV=`change in volume
Hence, negative sign implies that when the pressure increases, volume decreases and vice-versa.