Physics Test - ...

In a transformer 220 A.C. voltage is increased to 2200 volts. If the number of turns in the secondary are 2000, then the number of turns in the primary will be

In a photo electric experiment the maximum velocity of photo electons emitted

Two wires of same metal have the same length but their cross sections are in the ratio 3:1. They are joined in series. The resistance of the thicker wire is 10 Ω. The total resistance of the combination is

If elements with principal quantum number n > 4 were not allowed in nature, then, the number of possible elements would be

If a cell of constant electromotive force produces the same amount of heat during the same time in two independent resistances R₁ and R₂, when connected separately one after the other, across the cell, then the internal resistance of the cell is

A wire of radius r has resistance R. If it is stretched to a radius of 3r/4, its resistance becomes

Optical fibres uses the phenomenon of

The energy required to charge a parallel plate condenser of plate separation d and plate area of cross-section A such that the uniform electric field between the plates is E, is

Determine the current drawn from a 12 v supply with internal resistance 0.5Ω by the infinite network shown in the figure . Each resistor has Ω resistance

A cell whose e.m.f. is 2V and internal resistance is 0.1Ω, is connected with a resistance of 3.9Ω. The voltage across the cell terminal will be