List of top Physics Questions

The relative angular speed of hour hand and minute hand of clock is
According to Boyle's law, the product PV remains constant. The SI unit of PV is same as that of
The period of oscillation of a simple pendulum is \(T = 2π(L/g)^{1/2}\). Measured value of 'L' is 10 cm known to 1 mm accuracy and time for 100 oscillations is 50 second, using a watch of 1 second resolution. The percentage error in the measurement of 'g' is
The vector sum of the two forces \(\overset{⃗}{A}\) and \(\overset{⃗}{B}\) is perpendicular to their vector difference. Hence forces \(\overset{⃗}{A}\) and \(\overset{⃗}{B}\) are
In energy band diagram of insulators, a band gap and the conduction band is respectively
In common emitter mode of transistor, the d.c. current gain is \(20\), the emitter current is \(7\) mA. The collector current is
According to de-Broglie hypothesis, the ratio of the wave-length of a photon and that of an electron having same energy 'E' is (m = mass of electron, c = velocity of light)
In Bohr's theory of hydrogen atom, 'r' is the radius of the orbit, 'V' is the speed of electron and E is the total energy of the electron. Out of the following which physical quantity is inversely proportional to principal quantum number?
Photoelectrons are emitted from two similar metal plates when wavelengths \(λ_1\) and \(λ_2\) are incident on them (\(λ_1 = 1.5λ_2\)). If maximum kinetic energy of emitted photoelectrons is \(E_1\) and \(E_2\) respectively then
Bohr model is applied to a particle of mass 'm' and charge 'q' moving in a plane under the influence of a transverse magnetic field B. The energy of the charged particle in the \(n^{th}\) level will be (h=Planck's constant)
In the case of NAND gate, if A and B are inputs and Y is the output then
Alternating current of peak value \((\frac{2}{π})\) A flows through the primary coil of a transformer. The coefficient of mutual inductance between primary and secondary coils is \(1\) H. The peak em.f. induced in secondary coil is (Frequency of a. c. is \(50\) Hz)
Converging lens of telescope \(5\) cm in diameter has focal length \(25\) cm. In the focal plane of the lens the distance between the centres of the Fraunhofer diffraction pattern is (wavelength of light used = \(5000\) Å, Rayleigh's criterion is satisfied)
A thin prism in air produces the angle of minimum deviation \(δ\). If the prism is immersed in water, the angle of minimum deviation for the same ray is (refractive index of water is \(4/3\) and that of glass prism is \(3/2\))
In biprism experiment, the \(4^{th}\) dark band is formed opposite to one of the slits. The wavelength of light used is (D=distance between source and screen, d= the distance between the slits)
In Young's double slit experiment, in an interference pattern, a minimum is observed exactly in front of one slit. The distance between the two coherent sources is 'd' and 'D' is the distance between source and screen. The possible wavelengths used are inversely proportional to
In an a.c. circuit containing L, C and R in series, the ratio of apparent power to the true power is
(Z= impedance of the circuit and R= resistance )
In series LCR circuit, resistance is \(18 \Omega\) and impedance \(33 \Omega\). An r.m.s. Voltage of \(220\) V is applied across the circuit. The true power consumed in a c. circuit is
An ideal transformer converts \(220\)V a.c. to \(3.3\) KV a.c. to transmit a power of \(4.4\) KW. If primary coil has \(600\) turns then alternating current in the secondary coil is
A light bulb connected in series with a capacitor and an a.c.source is glowing with certain brightness. On reducing the value of capacitance and frequency respectively, the brightness of the bulb
A coil having 'n' turns and resistance 'R' is connected with a galvanometer of resistance '2R'. This combination is moved in time 't' from flux \(φ_1\) to \(φ_2\) Wb. The induced current in the circuit is
Two parallel wires of equal lengths are separated by a distance of \(3\) m from each other. The currents flowing through first and second wire is \(3\) A and \(4.5\) A respectively in opposite directions. The resultant magnetic field at mid point of both the wires is (\(μ_0\)=permeability of free space)
A circular coil of N turns and diameter D carries current I. It is unwound and rewound to make another coil of diameter 2D, current I remaining the same. The ratio of magnetic moments of the original coil to the new coil is
In potentiometer experiment, null point is obtained at a particular point for a cell on potentiometer wire 'x' cm long. If length of potentiometer wire is increased by few cm without changing the cell, the balancing length will (Driving source is not changed)
A source of sound is moving towards a stationary observer with velocity '\(V_S\)' and then moves away with velocity '\(V_S\)'. Assume that medium through which the sound waves travel is at rest. If 'V' is the velocity of sound and 'n' is the frequency emitted by the source then the difference between the apparent frequencies heard by the observer is