Select the most appropriate option to fill in the

Which metal exhibits the highest electrical conductivity among the following?

Which of the following is the time taken for one complete oscillation of a sound wave in the density of the medium?

The Atom Bomb dropped in Nagasaki is an uncontrolled nuclear fission made up of:

What term describes the rate of change of velocity? 

If input frequency of a full wave rectifier be n, then output frequency would be-

What is the SI unit for measuring speed?

Pulsars are :

In which form is the supplied heat energy stored during change in temperature of substance?

‘Therm' is the unit of –

Which of the following determines the loudness or softness of the sound?