List of top Physics Questions

In the circuit shown, the ratio of the quality factor and the band width is
(Given: band width = R/L)

Resistances are joint as shown in the figure. In the balanced condition, the current \(I\) drawn from the battery is

The electric potential at the center of two concentric half rings of radii \(R_1\) and \(R_2\), having same linear charge density \(λ\) is (\(ε_0\) = permittivity of free space)

The velocity time graph of a body moving in a straight line is shown in a figure. The ratio of displacement to distance travelled by the body in time \(0\) to \(10\) s is

What does the following combination of gates produce?

In the circuit shown below, the ac source has voltage \(V = 30cos(ωt)\) volt with \(ω = 2000\) rad/s. What will be the amplitude of the current?

The following figure represents two bulbs \(B_1\) and \(B_2\), resistor R and an inductor L. When the switch S is turned off, which of the following statement is true?

A long rectangular conducting loop of width '\(l\)' mass '\(m\)' and resistance '\(R\)' is placed partly in a perpendicular magnetic field '\(B\)'. With what velocity should it be pushed downwards so that it may continue to fall without any acceleration? (\(g\) = acceleration due to gravity)

Which of the following figure best represents the variation of magnetic susceptibility (\(χ\)) with temperature for a diamagnetic substance?

Following figure indicates the electric potential V as a function through 4 regions on x-axis. Which of the following is correct for the electric field E in these regions?

An ideal gas undergoes cyclic process ABCDA as shown in given p-V diagram. What is the magnitude of amount of work done by the gas?

Three identical heat conducting rods are connected in series as shown in the figure. The rods on the side have thermal conductivity \(2K\) while that in the middle has thermal conductivity \(K\). The left end of the combination is maintained at temperature \(3T\) and the right end at \(T\). The rods are thermally insulated from outside. In steady state, temperature at the left junction is \(T_1\) and that at the right junctions is \(T_2\). The ratio \(T_1/T_2\) is

A vessel contains oil (density \(= 0.8\text{ gm}/\text{cm}^3\)) over mercury (density \(= 13.6\text{ gm}/\text{cm}^3\)). A homogeneous sphere floats with half of its volume immersed in mercury and the other half in oil. The density of the material of the sphere in \(\text{gm}/\text{cm}^3\) is

A wire AB is carrying steady current \(I_1\) and is kept on the table. Another wire CD carrying current \(I_2\) is held directly above as shown in figure. When the wire CD is left free and it remains suspended at its position, its mass per unit length is (g=acceleration due to gravity, \(μ_0\) = permeability of free space)

In the following network, the current flowing through \(15 \Omega\) resistance is

An alpha particle of energy \(\dfrac{1}{2}\) mv\(^2\) bombards a heavy target nucleus of charge Ze. Then, the distance of closet approach for the alpha particle will be proportional to

If 200 MeV energy is released in the fission of a single nucleus of \({}^{235}_{92}U\), how many fissions per second must occur to produce a power of 1 kW?

Match List-I with List-II. Assume that the Si intrinsic semiconductor has \(5 \times 10^{28}\) atoms/m\(^3\). (Given: the intrinsic concentration of electrons in the semiconductor is \(10^{16}\ \text{m}^{-3}\)).

	LIST-I		LIST-II
A	When it is doped with 2 ppm concentration of a pentavalent atom, \(n_e\) is	I	\(4.0 \times 10^{8}\ \text{m}^{-3}\)
B	When it is doped with 2 ppm concentration of a pentavalent atom, \(n_h\) is	II	\(2.5 \times 10^{23}\ \text{m}^{-3}\)
C	When it is doped with 5 ppm concentration of a pentavalent atom, \(n_e\) is	III	\(10^{9}\ \text{m}^{-3}\)
D	When it is doped with 5 ppm concentration of a pentavalent atom, \(n_h\) is	IV	\(10^{23}\ \text{m}^{-3}\)

Choose the correct answer from the options given below:

For a heavily doped n-type semi-conductor, donor level lies

If the forward bias voltage in a diode is increased, the width of the depletion region

The maximum wavelength of electromagnetic radiation which can create a hole-electron pair in the semiconductor Ge is: (Given, the band gap of Ge is 0.72 eV)

In Bohr's model of hydrogen atom, which of the following is an integral multiple of \(\dfrac{h}{2\pi}\) ?

Match the LIST-I with LIST-II (Symbols have their usual meaning)

LIST-I Spectral series of Hydrogen	LIST-II Wave Number
A. Lyman series	I. \(\bar{v} = R\left[\dfrac{1}{1^2} - \dfrac{1}{n_2^2}\right]\)
B. Paschen series	II. \(\bar{v} = R\left[\dfrac{1}{2^2} - \dfrac{1}{n_2^2}\right]\)
C. Balmer series	III. \(\bar{v} = R\left[\dfrac{1}{3^2} - \dfrac{1}{n_2^2}\right]\)
D. Brackett series	IV. \(\bar{v} = R\left[\dfrac{1}{4^2} - \dfrac{1}{n_2^2}\right]\)

Choose the correct answer from the options given below:

A monochromatic source emitting light of 600 nm, has a power output of 66 W. The number of photons emitted by the source per second is (Given, Plank's constant h = 6.6 \(\times\) 10\(^{-34}\) Js)

An electron and a photon each have the same de-Broglie wavelength of 1.0 nm. The ratio of their linear momenta is