Which of the following are correct?

Options

A. The shear modulus of a liquid is infinite
B. Bulk modulus of a perfectly rigid body is infinite.
C. When length fo a bar is increased by strechtingh it, it's volume must decreases.
D. When length of a bar is increased by streching it, its volume must remain same.

Answer

A, B

Explanation

As liquid has no fixed shape and it cannot bear any tangential stress, hence share modulus of liquid is infinite `(Delta)/(v) = (Delta L)/(L) [1 - 2sigma]`
When `sigma` is position ratio. Therefore when a bar a stretched it volume may increses, decreases of reamin same.