Alternating Current — Physics STD 12 Science — Question

The amplitude of the sinusoidally oscillating electric field of a plane wave is 60v/m. Then the amplitude of the magnetic field is:

Magnitude of intensity of magnetic field at the center of any circular current carrying conductor is:

The process by which a heavy nucleus splits into light nuclei is known as

(a) Fission

(b) α- decay

(c) Fusion

(d) Chain reaction

Making a light wave vibrate in only one plane is known as:

Emission of electrons starts on incidence of green light from a metal. Which of the following group of colours will cause emission of electrons due to light?

The capacity of a parallel plate condenser is 10μF  without dielectric. Dielectric of constant 2 is used to fill half the distance between the plates, the new capacitance in μF is

(a) 10

(b) 20

(c) 15

(d) 13.33

Isotopes of an element contain:

A moving coil galvanometer has 150 equal divisions. Its current sensitivity is 10 divisions per milliampere and voltage sensitivity is 2 divisions per millivolt. In order that each division reads 1 volt, the resistance in ohms needed to be connected in series with the coil will be

(a) 99995

(b) 9995

(c)

(d)

A resistor of resistance R is connected to an ideal battery. If the value of R is decreased, the power dissipated in the resistor will:

A proton moving with a velocity, 2.5  , enters a magnetic field of intensity 2.5T making an angle 30°  with the magnetic field. The force on the proton is

(a) 3

(b) 5

(c) 6

(d) 9