Electromagnetic Waves — Physics STD 12 Science — Question

In the Young's double slit experiment, if the phase difference between the two waves interfering at a point is ∅, the intensity at that point can be expressed by the expression (Where A and B depend upon the amplitudes of the two waves)

(a) I =

(b) I =

(c) I = A + Bcos

(d) I = A + B Cos∅

A capacitor with no dielectric is connected to a battery at t = 0. Consider a point A in the connecting wires and a point B in between the plates.

1. There is no current through A.
2. There is no current through B.
3. There is a current through A as long as the charging is not complete.
4. There is a current through B as long as the charging is not complete.

The dimensions of magnetic flux are

(a)

(b)

(c)

(d)

A 50V battery is connected across a 10 ohm resistor. The current is 4.5 amperes. The internal resistance of the battery is

(a) Zero

(b) 0.5 ohm

(c) 1.1 ohm

(d) 5.0 ohm

Two bodies at different temperatures are mixed in a calorimeter. Which of the following quantities remains conserved?

1. Sum of the temperatures of the two bodies.
2. Total heat of the two bodies.
3. Total internal energy of the two bodies.
4. Internal energy of each body.

The length of a conductor is doubled and its radius is halved, its specific resistance is:

Which error is removed when the known and unknown resistances are interchanged in a Meter Bridge?

In an electromagnetic wave, the direction of the magnetic induction B is

Assertion  :   In photoelectric effect, on increasing the intensity of light, both the number of electrons emitted and kinetic energy of each of them get increased but photoelectric current remains unchanged.

Reason     : The photoelectric current depends only on wavelength of light.

(a) If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.

(b) If both assertion and reason are true but reason is not the correct explanation of the assertion.

(d) If the assertion and reason both are false.

If threshold wavelength for sodium is 6800Å then the work function will be

(a) 1.8 eV

(b) 2.5 eV

(c) 2.1 eV

(d) 1.4 eV