How is energy transferred?

The primary and secondary coils of a transformer do not have any electrical contact. How is then electrical energy transferred from primary to secondary ?

(a) Name a device which helps to maintain potential difference across a conductor (say, a bulb). (b) If a potential difference of 10V causes a current of 2A to flow for 1 minute, how much energy is transferred?

If the energy transferred to a tertiary consumer in a food chain is 10 J, how much energy was available to the primary consumer ?

Explain given cases related to energy transfer between the system and surrounding – energy transferred (Q) gt 0

Explain given cases related to energy transfer between the system and surrounding – energy transferred (Q) = 0

Explain given cases related to energy transfer between the system and surrounding – energy transferred (Q) lt 0

A lab sample of gas is taken through cyclic abca shown in the P-V diagram of fig 21-22 the net work done is + 1.5 J . Along paths Ab the change in the internal energy is +3.0 and the magnitude of the work done is 5.0 J Along path ca the energy transferred to the gas as heat is + 2.5 J . How much energy is transferred as heat along (a) path ab and (b) path bc ?