Magnetism And Matter — Physics STD 12 Science — Question

In a wheatstone bridge in the battery and galvanometer are interchanged then the deflection in galvanometer will:

If the kinetic energy of a free electron doubles, its de-Broglie wavelength changes by the factor

(a)

(b)

(c)

(d) 2

A particle A has charge +q and a particle B has charge +4q with each of them having the same mass m. When allowed to fall from rest through the same electric potential difference, the ratio of their speed   will become

(a) 2 : 1

(b) 1 : 2

(c) 1 : 4

(d) 4 : 1

Which of the following has zero average value in a plane electromagnetic wave?

The binding energies per nucleon for a deuteron and an α- particle are x₁ and x₂ respectively. What will be the energy Q released in the reaction  

(a) 4

(b) 4

(c) 2(

(d) 2

If an insulated non-conducting sphere of radius R has charge density ρ. The electric field at a distance r from the centre of sphere (r < R)  will be

(a)

(b)

(c)

(d)

As shown in the figure, a very thin sheet of aluminium is placed in between the plates of the condenser. Then the capacity

(a) Will increase	(b) Will decrease
(c) Remains unchanged	(d) May increase or decrease

A cube of side b  has a charge q at each of its vertices. The electric field due to this charge distribution at the centre of this cube will be

(a)

(b)

(c)

(d) Zero

Three glass prisms A, B and C of same refractive index are placed in contact with each other as shown in figure, with no air gap between the prisms. Monochromatic ray of light OP passes through the prism assembly and emerges as QR. The conditions of minimum deviation is satisfied in the prisms

(a) A and C	(b) B and C
(c) A and B	(d) In all prisms A, B and C

According to the electromagnetic wave theory, light consists of electric and magnetic fields which are_____________.