List of top Physics Questions

A force of \(3\hat{i}+2\hat{j}-\hat{k}\) N acts on a particle with position vector \(\hat{i}+\hat{j}-\hat{k}\) m. The magnitude of torque of given force is

A satellite is revolving around a planet in a circular orbit close to its surface. Let \(ρ\) be mean density and \(R\) be the radius of the planet; then the period of the satellite is
(\(G\) = Universal constant of gravitation).

Two particles of masses \(2\) g and \(4\) g are situated at the opposite ends, A and B of a wooden bar respectively. Let \(l(AB) = 9\) cm. The center of mass of the system will be

A body of mass 'm' attached at the end of a string is just completing the loop in a vertical circle. The apparent weight of the body at the lowest point in its path is
(\(g\) = gravitational acceleration)

A particle is performing U.C.M. along a circle of radius \(R\). In half the period of revolution, its displacement and distance covered are respectively

A cuboid has volume \(V = l\times l\times \sqrt{l}\), where \(l\) is the length of one side. When the length \(l\) is measured by a meter scale of least count \(1\,\text{mm}\), the relative percentage error in the measurement of its volume is \(6.25\%\). Then the relative percentage error in measurement of its length and the value of the length \(l\) is

The equation of the trajectory of a ball projected at an angle \(θ\) with the horizontal, is given as \(y = x-\frac{gx^2}{2}\)
The initial velocity of the ball is
[Given : \(tan45^{\circ} = 1\), \(cos45^{\circ} = \frac{1}{\sqrt{2}}\) ]

A stone of mass \(40\) g is tied to a light inextensible string of length \(50\) cm and whirled in a vertical circle at the rate of \(30\) revolutions per minute. The tension in the string when it is at the lowest point of the circle is
(Take gravitational acceleration, \(g = 10\,\text{m/s}^2\) and \(π^2 = 10\))

In n-type semiconductor
A) pentavalent impurity are dopants and holes are majority carriers.
B) trivalent impurity are dopants and electrons are minority carriers.
C) pentavalent impurity are dopants and electrons are majority carriers.
D) trivalent impurity are dopants and holes are majority carriers.

The material used for solar cell should have band gap
(A) equal to zero.
(B) equal to \(0.08\) eV.
(C) between \(1.0\) eV to \(1.8\) eV.
(D) equal to \(2\) eV.

A radioactive sample has half-life of \(5\) years. The percentage of fraction decayed in \(10\) years will be

For a two input logic gate, when the inputs are 'zero' and 'zero' the output is 'one'. When the inputs are 'one' and 'zero' the output is 'zero'. The type of logic gate is

The shortest wavelength in the Balmer series of hydrogen atom is equal to the shortest wavelength in the Brackett series of a hydrogen like atom of atomic number 'Z'. The value of 'Z' is

In Young's double slit experiment, for the \(n^{\text{th}}\) dark fringe (\(n = 1,2,3,\ldots\)) the phase difference of the interfering waves in radian will be

In a single slit diffraction pattern, the distance between the plane of the slit and the screen is \(1.4\) m. The width of the slit is \(0.66\) mm. The second maximum is formed at the distance of \(2.8\) mm from the center of the screen. The wavelength of light used is

According to Einstein's photoelectric equation, the graph of the kinetic energy of the emitted photoelectrons versus the frequency of incident radiation gives a straight line whose slope

A photoelectric surface is illuminated successively by monochromatic light of wavelength \(λ\) and \((λ/3)\). If the maximum kinetic energy of the emitted photo electrons in the second case is \(4\) times that in the first case, the work function of the surface of the material is (\(h\) = Planck's constant, \(c\) = speed of light)

An alternating voltage \(e = 150\sqrt{2}sin100t\) volt is applied to a capacitor of capacity \(2 μ\text{F}\). The root mean square value of current in the circuit is

In Young's double slit experiment, the wavelength of light used is \(λ\). The intensity on the screen at a point for path difference '\(λ\)' is 'X'. The intensity at the point for path difference \((\frac{λ}{6})\) is (\(cos180^{\circ} = -1\), \(cos30^{\circ} = \frac{\sqrt{3}}{2}\))

In an LCR circuit at resonance, the a.c. source current is
A) maximum in a series LCR circuit only.
B) maximum in a parallel LCR circuit only.
C) maximum in both series and parallel LCR circuits.
D) minimum in both series and parallel LCR circuits.
The correct answer is

For a series LCR circuit inductive reactance \(X_L\) is equal to resistance \(R\) and also equal to twice the capacitive reactance \(X_C\). The impedance of the circuit and the phase difference between voltage V and current i are respectively

A glass slab of thickness \(6.0\) cm is placed on the piece of paper on which an inkdot is marked. By how much distance would an inkdot appear to be raised? The velocity of light in glass is \(2\times 10^8\text{ ms}^{-1}\) and that in air is \(3\times 10^8\text{ ms}^{-1}\).

Magnetic flux linked with the coil in weber is given by the equation \(\Phi = 5t^2+6t+11\). The e.m.f. induced in the coil in the \(5^{\text{th}}\) second will be

A diamagnetic liquid is filled in a U-tube. One arm of a U-tube is placed in an external magnetic field with the meniscus in line with the field. The level of the liquid in that arm will

The frequency of oscillation of a small magnet in a magnetic field of induction 'B' is '\(n\)'. If the frequency of oscillations of the same magnet in a field of induction 'X' falls to \((\frac{n}{3})\), the value of 'X' is