Physics Test 21...

When a rubber band is stretched by a distance x, it exerts a restoring force of magnitude F = ax + bx², where a and b are constants. The work done in stretching the unstretched rubber band by L is

Assertion It is not possible for a system, unaided by an external agency to transfer heat from a body at lower temperature to another body at higher temperature.

Reason According to Clausius statement, \"No process is possible whose sole result is the transfer of heat from a cooled object to a hotter object.

In a capacitor which is initially charged such that the left plate of capacitor has charge +Q and the right plate has zero charge at time t = 0 s. The total charge on the right plate after closing the switch will be

Consider a common-base amplifier made by a PNP transistor, the current gain is 0.96 and emitter current is 7.2 mA. The base current is

In an AC circuit, which has unknown electrical devices connected in series having resistance 3 Ω, the power factor is 3/5. The resistance of circuit is

For the given combination of gates, if the logic gates of inputs A, B and C are as follows. A=B=C =0 and A=B=1, C=0. Then, the logic gates of output D are

Given combination of NAND gates will be equivalent to,

The collector current is 10 mA in n-p-n transistor. If 80% electrons emitted reach the collector then:

Find the angular speed of the meter stick, when a person throws it such that the centre of the stick is moving with a speed of 10 m s^-1 vertically upwards & left end of stick with a speed of 20 m s^-1 vertically upwards.

Find the current flowing in the primary coil, if the secondary coil of an ideal step down transformer is delivering 500 W power at 12.5 A current. The ratio of turns in the primary to the secondary is 5:1.