SSC JE Electrical Engineering 2015
For the following questions answer them individually
The magnitude of AT required to establish a given value of flux in the air gap will be much greater than that required for iron part of a magnetic circuit, because:
The area of the hysteresis loop will be least for one of the following materials.It is:
A current of 2A passes throught a coil of 350 turn wound on a ring of mean diameter 12cm. The flux, density established in the ring is 1.4 $$\frac{wb}{m^{2}}$$ . Find the value of relative permeability of iron:
A bar of iron 1 $$cm^{2}$$ in cross-section has 10-4 Wb of magnetic flux in it. If $$ \mu $$r = 2000 what is the magnetic field intensity in the bar?
One sine wave has a period of 2 ms, another has a period of 5 ms, and other has a period of 10 ms. Which sine wave is changing at a faster rate?
. In a pure inductive circuit if the supply frequency is reduced to $$\frac{1}{2}$$, the current will:
There are 3 lamps 40W, 100W and 60W. To realise the full rated power of the lamps they are to be connected in:
Two lamps, Green (G) and Red (R) are connected in a motor circuit as shown in the figure. The conditions under which the lamps will burn are, (supply is available at terminals A & B):
If a dynamometer type wattmeter is connected in an ac circuit, the power indicated by the wattmeter will be
