Physics Test - ...

The depletion layer in a \(p-n\) junction diode is \(10^{-6}m\) wide and its knee potential is \(0.5 V\). What is the inner electric field in the depletion region?

A train of length \(80 m\) is moving with a uniform velocity of \(25 m/sec\). The time taken by the train to cross a bridge \(120 m\) long is

A shell at rest, at the origin explodes into three fragments of masses 1 kg, 2 kg and m kg. The pieces weighing 1 kg and 2 kg fly off with a speed of 5 ms–1along x– axis and 6 ms–1along y– axis respectively. If the 'm' kg piece flies off with a speed of 6.5 ms–1, what must be the total mass of the shell?

For the given circuit to act as a full-wave rectifier, the AC input should be connectedacross ..i... and ..ii... and the DC output should appear across ...iii... and ...iv....

i, ii, iii and iv, respectively, are

Two electric bulbs rated P1watt V volt, and P2watt V volt are connected in parallel, and applied across V volt. The total power will be

The Thermo emf produced in a thermocouple is 3μV/oC. If the temperature of the cold junction is 20oC and the Thermo emf is 0.3 mV, the temperature of the hot junction is-

Two particles start simultaneously from the same point and move along two straight lines, one with uniform velocity \(\vec u\)and the other from rest with uniform acceleration \(\vec f\). Let \(\alpha\)be the angle between their directions of motion. The relative velocity of the second particle w.r.t. first is least after a time of

A nucleus decays by+emission, followed by-emission. If the atomic and mass numbers of the parent nucleus are Z and A, respectively, then the corresponding numbers for the daughter nucleus are

An engine pumps up 100 kg of water through a height of 10 m in 5s. Given that the efficiency of engine is 60%. If g = 10 ms^-2, the power of the engine is :

Two bodies of masses \(m\) and \(4m\) are moving with equal momentum. The ratio of their kinetic energy is