List of top Physics Questions

The graph showing correct variation of photo current with intensity of incident light:

One light year is equals to______.

An infinite line charge produces an electric field of 9 × 10⁶ N/C at a distance of 20 cm. The linear charge density will be :

Which of the following graph correctly shows the relation between photoelectric current (I) and wavelength (λ) of incident radiation

A radioactive isotope phosphorous-32 has an initial activity 10μCi and has half life of 14 days. What is the activity of the source after 42 days?

A spherical conducting shell of inner radius r₁ and outer radius r₂ has a charge Q. A charge q is placed at the centre of the shell. The surface charge density on outer surface of the shell is:

Which of the following is/are responsible for the formation of Rainbow?
(A) Dispersion of light
(B) Interference of light
(C) Reflection of light
(D) Refraction of light
Choose the correct answer from the options given below:

C.V. Raman got Nobel Prize in 1930 for his discovery of:

The change of gaseous state directly to solid state without going through liquid state is called_____

Two charges 5 µC and -2 µC (with no external field) are placed at (-9 cm, 0, 0) and (9 cm, 0, 0) respectively. The work required to separate the two charges infinitely away from each other is :

Choose the correct statements:
(A) A nuclide is represented as \(^Z_AX\)
(B) Nuclids with same number of protons are called isotopes
(C) a-ray scattering experiments allow determination of the nuclear radius
(D) Nuclids with same number of neutrons are called isotones
(E) The nuclear force distinguishes between neutron and proton
Choose the correct answer from the options given below:

What is the wavelength of light for the least energetic photon emitted in the Lyman series of the hydrogen atom spectrum lines?
(Take h=6.63×10^-34Js; c=3×10⁸ ms^-1; e=1.6×10^-19C)

Which of the following statements are correct for a transistor action ?
(A) The input resistance depends upon the current I_C in the transistor
(B) Collector currents is equal to the sum of base current and emitter current
(C) The emitter junction is forward biased
(D) The collector junction is reverse biased
(E) Both the emitter junction as well as the collector junction are forward biased
Choose the correct answer from the options given below:

At what speed should a galaxy move with respect to earth so that spectral line of 600.0 nm appears as 600.6 nm?

For a medium with permittivity (e) and permeability (µ), the speed of light (v) is given by:

Match LIST I with LIST II

LIST I Device		LIST II  Purpose
A	Microphone	I	Used in vehicles to measure distance
B	Audiometer	II	For measuring the force and velocity of wind
C	Odometer	III	Converts sound waves to electrical vibrations
D	Anemometer	IV	Measures intensity of sound

Choose the most appropriate answer from the options given below:

The forbidden energy gaps in conductors, semiconductors and insulators are (E_g)_c, (E_g)_s and (E_g)₁ respectively. What is the relation among them ?

The potential of a uniformly charged spherical shell at a point r/2 from its centre is 5 V. The potential at its surface is:
(Given radius of shell = r)

Consider two different hydrogen atoms. The electron in each atom is in first excited state. According to Bohr's model, electrons will have:

Let us consider interference between two sources of intensities I and 4I. What will be the intensity at points where the phase difference is π?

Match List I with List II

List-I		List-II
(A)	To slow down fast moving neutrons	(I)	Thermal neutrons
(B)	A neutron or a proton	(II)	Fission
(C)	Slow neutrons	(III)	Moderator
(D)	Neutron induced nuclear reaction	(IV)	Nucleon

Choose the correct answer from the options given below:

A parallel beam of monochromatic light of wavelength 460 nm passes through a long slit of width 0.1 mm. What is the angular divergence in which most of the light is diffracted?

The shape of graph between 1/u and 1/v in case of a convex lens is:

The logic gate realised using p-n junction diodes in the given figure is:

The capacitance of capacitor increases when :
(A) its charge increases
(B) its supply voltage decreases
(C) common area of the plates increases
(D) separation between the plates decreases
Choose the correct answer