Electromagnetic Waves — Physics STD 12 Science — Question

Electromotive Force (EMF) may be defined as:

Young’s double slit experiment is performed with light of wavelength 550 nm. The separation between the slits is 1.10 mm and screen is placed at distance of 1 m. What is the distance between the consecutive bright or dark fringes (a) 1.5 mm(b) 1.0 mm(c) 0.5 mm(d) None of these

The resultant capacitance of given circuit is

The graph shows the variation of magnetic field (B)with distance (r) from a long current carrying wire is-

A potentiometer having the potential gradient of 2 mV/cm is used to measure the difference of potential across a resistance of 10 ohm. If a length of 50 cm of the potentiometer wire is required to get the null point, the current passing through the 10 ohm resistor is (in mA)(a) 1(b) 2(c) 5(d) 10

The Boolean expression for NOR gate, is :

The collector plate in an experiment on photoelectric effect is kept vertically above the emitter plate. Light source is put on and a saturation photocurrent is recorded. An electric field is switched on which has a vertically downward direction.

1. The photocurrent will increase.
2. The kinetic energy of the electrons will increase.
3. The stopping potential will decrease.
4. The threshold wavelength will increase.

The sensitivity of a tangent galvanometer is increased if(a) Number of turn decreases (b) Number of turn increases(c) Field increases(d) None of the above