(i) Define heat capacity of a substance.

(ii) Write the SI unit of heat capacity.

(iii) What is the relationship between heat capacity and specific heat capacity of a substance?

The diagram alongside shows three resistors connected across a cell of e.m.f. 1.8 V and internal resistance r. Calculate:

(i) Current through 3 Ω resistor.

(ii) The internal resistance r.

(i) When a tuning fork [vibrating] is held close to ear, one hears a faint hum. The same [vibrating tuning fork] is held such that it's stem is in contact with the table surface, then one hears a loud sound. Explain.

(ii) A man standing in front of a vertical cliff fires a gun. He hears the echo after 3.5 seconds. On moving closer to the cliff by 84 m, he hears the echo after 3 seconds. Calculate the distance of the cliff from the initial position of the man.

The diagram below shows the core of a transformer and it's input and output connections

(i) State the material used for the core.

(ii) Copy and complete the diagram of the transformer by drawing input and output coils.