List of top Physics Questions

Water falls from a height of 60 m at the rate of 15 kg/s to operate a turbine. The losses due to frictional force are 10% of the input energy. How much power is generated by the turbine (g=10 m/s²)

Polar molecules are the molecules :

A thick current-carrying cable of radius ‘R’ carries current ‘I’ uniformly distributed across its cross-section. The variation of magnetic field B(r) due to the cable with the distance ‘r’ from the axis of the cable is represented by 

A parallel plate capacitor has a uniform electric field ‘ E → ’ in the space between the plates. If the distance between the plates is ‘d’ and the area of each plate is ‘A’, the energy stored in the capacitor is : (ε₀=permittivity of free space)

A capacitor of capacitance ‘C’, is connected across an ac source of voltage V, given by V=V₀sinωt The displacement current between the plates of the capacitor, would then be given by

A lens of large focal length and large aperture is best suited as an objective of an astronomical telescope since

A radioactive nucleus \(_{Z}^{A}\textrm{X}\) undergoes spontaneous decay in the sequence \(_{Z}^{A}\textrm{X}\)\(\rightarrow\)_Z-1B\(\rightarrow\)_Z-3C\(\rightarrow\)_Z-2D, where Z is the atomic number of element X. The possible decay particles in the sequence are

A body is executing simple harmonic motion with frequency ‘n’, the frequency of its potential energy is

A particle is released from height S from the surface of the Earth. At a certain height, its kinetic energy is three times its potential energy. The height from the surface of the earth and the speed of the particle at that instant are respectively

The escape velocity from the Earth’s surface is v. The escape velocity from the surface of another planet having a radius, four times that of Earth and same mass density is

For the given circuit, the input digital signals are applied at the terminals A, B and C. What would be the output at the terminal y?

A nucleus with mass number 240 breaks into two fragments each of mass number 120, the binding energy per nucleon of unfragmented nuclei is 7.6 MeV while that of fragments is 8.5 MeV. The total gain in the Binding Energy in the process is

An inductor of inductance L, a capacitor of capacitance C and a resistor of resistance ‘R’ are connected in series to an ac source of potential difference ‘V’ volts as shown in the figure. The potential difference across L, C and R is 40 V, 10 V and 40 V, respectively. The amplitude of current flowing through LCR series circuit is 10√2 A. The impedance of the course is

A uniform rod of length 200 cm and mass 500 g is balanced on a wedge placed at the 40 cm mark. A mass of 2 kg is suspended from the rod at 20 cm and another unknown mass ‘m’ is suspended from the rod at the 160 cm mark as shown in the figure. Find the value of ‘m’ such that the rod is in equilibrium. (g=10 m/s²)

The electron concentration in an n-type semiconductor is the same as the hole concentration in a p-type semiconductor. An external field (electric) is applied across each of them. Compare the currents in them

Twenty seven drops of same size are charged at 220 V each. They combine to form a bigger drop. Calculate the potential of the bigger drop

Consider the following statements (A) and (B) and identify the correct answer. 
(A) A zener diode is connected in reverse bias when used as a voltage regulator. 
(B) The potential barrier of the p-n junction lies between 0.1 V to 0.3 V.

Column - I gives certain physical terms associated with the flow of current through a metallic conductor. Column - II gives some mathematical relations involving electrical quantities. Match Column - I and Column - II with appropriate relations 

Two charged spherical conductors of radius R₁ and R₂ are connected by a wire. Then the ratio of surface charge densities of the spheres (σ₁ /σ₂ ) is

A particle of mass ‘m’ is projected with a velocity v=kV_e(k < 1) from the surface of the earth. (V_e=escape velocity) The maximum height above the surface reached by the particle is

A car starts from rest and accelerates at 5 m/s² . At t=4 s, a ball is dropped out of a window by a person sitting in the car. What is the velocity and acceleration of the ball at t=6 s? (Take g=10 m/s²)

A small block slides down on a smooth inclined plane, starting from rest at time t=0. Let Sn be the distance traveled by the block in the interval t=n−1 to t=n. Then, the ratio \(\frac{S_n}{S_{(n+1)}}\)

A series LCR circuit containing a 5.0 H inductor, 80 µF capacitor and 40 Ω resistor is connected to a 230 V variable frequency ac source. The angular frequencies of the source at which power transferred to the circuit is half the power at the resonant angular frequency are likely to be