Electromagnetic Induction — Physics STD 12 Science — Question

The magnetic field due to a current carrying circular loop of radius 3 cm at a point on the axis at a distance of 4 cm from the centre is 54 mT. What will be its value at the centre of the loop

The earth’s magnetic field at a given point is 0.5  . This field is to be annulled by magnetic induction at the center of a circular conducting loop of radius 5.0cm. The current required to be flown in the loop is nearly

Which of the following quantities increase when wavelength is increased? Consider only the magnitudes.

On heating a liquid, the refractive index generally

When a certain circuit consisting of a constant e.m.f. E an inductance L and a resistance R is closed, the current in, it increases with time according to curve 1. After one parameter (E, L or R) is changed, the increase in current follows curve 2 when the circuit is closed second time. Which parameter was changed and in what direction

A galvanometer of resistance 20 W is to be converted into an ammeter of range 1 A.  If a current of 1 mA produces full scale deflection, the shunt required for the purpose is

The diode used in the circuit shown in the figure has a constant voltage drop of 0.5 V at all currents and a maximum power rating of 100 milliwatts. What should be the value of the resistor R, connected in series with the diode for obtaining maximum current

In the following common emitter configuration an NPN transistor with current gain b = 100 is used. The output voltage of the amplifier will be