Class 12th

In the shown circuit, current through 4 Ω resistor is

A parallel plate capacitor is charged and then charging battery is disconnected. If the plates are now pulled apart with insulated handles

An ideal engine whose efficiency is 40%, receives heat at 500 K. If required efficiency is 50%, then intake temperature for the same exhaust temperature is

Choose the correct statement.

In a thermodynamic process, pressure of fixed mass of a gas is changed in such a manner that the gas releases 20 J of heat and 8 J of work is done on the gas. If initial internal energy of the gas was 40 J, what will be final internal energy?

Two rain drops reach earth from clouds with different terminal velocities having ratio 9 : 4. Then the ratio of their volumes is

If work done in increasing the size of rectangular soap film with dimensions 8 cm * 3.75 cm to 10 cm * 6 cm is 2 * 10^–4 J. The surface tension of film in newton per meter is

A wire can be broken by a load of 20 kg-wt. The force required to break wire of same material with twice the diameter will be

The height at which the weight of an object becomes (1/16)^thof its weight on the surface of earth is (R is radius of earth)

A body is released from height equal to radius R of the earth. The velocity of body with which it will strike the earth surface is