Wave Optics — Physics STD 12 Science — Question

Magnetic field inside a solenoid is:

No. of protons and neutrons in hydrogen atom are respectively __________ .

Consider a photon of a continuous X-ray coming from a Coolidge tube. Its energy comes from:

1. The kinetic energy of the striking electron.
2. The kinetic energy of the free electrons of the target.
3. The kinetic energy of the ions of the target.
4. An atomic transition in the target.

The threshold wavelength for photoelectric emission from a material is 5200 Å.  Photo-electrons will be emitted when this material is illuminated with monochromatic radiation from a

(a) 50 watt infrared lamp	(b) 1 watt infrared lamp
(c) 50 watt ultraviolet lamp	(d) Both (c) and (d)

A capacitor works in:

The work-function of a metal is:

Is the ratio of frequencies of UV rays and IR rays in the glass more than, less than or equal to 1?

When subjected to a transverse electric field, cathode rays move

(a) Down the potential gradient	(b) Up the potential gradient
(c) Along a hyperbolic path	(d) Along a circular path

Inductive reactance of a coil is expressed in.

The wavelength of maximum energy, released during an atomic explosion, was 2.93 × 10^–10 m. Given that the Wien's constant is 2.93 × 10^–3 m K, the maximum temperature attained must be of the order of

(a) 10–7 K

(b) 107 K

(c) 10–13 K

(d) 5.86 × 107 K