List of top Physics Questions

Two bodies of mass $4\,kg$ and $6\,kg$ are tied to the ends of a massless string. The string passes over a pulley which is frictionless (see figure). The acceleration of the system in terms of acceleration due to gravity (g) is :

Identify the function which represents a periodic motion

A wire of length L, area of cross section A is hanging from a fixed support. The length of the wire changes to \(L_1\) when mass M is suspended from its free end. The expression for Young’s modulus is:

A wire of length $L$ metre carrying a current of $I$ ampere is bent in the form of a circle. Its magnetic moment is,

The capacitance of a parallel plate capacitor with air as medium is $6\, \mu F$. With the introduction of a dielectric medium, the capacitance becomes 30 $\mu F.$ The permittivity of the medium is : $(\epsilon_0 = 8.85 \times 10^{-12} C^2N^{-1}m^{-2}$)

A ball is thrown vertically downward with a velocity of 20m/s from the top of a tower. It hits the ground after some time with a velocity of 80m/s. The height of the tower is : (g = $10m/s^2$)

The ratio of contributions made by the electric field and magnetic field components to the intensity of an electromagnetic wave is : (c = speed of electromagnetic waves)

An iron rod of susceptibility 599 is subjected to a magnetising field of 1200 A $m^{-1}$. The permeability of the material of the rod is : $(\mu_o = 4\pi \times 10^{-7} T\,m\,A^{-1})$

For which one of the following, Bohr model is not valid?

The number of protons, neutrons and electrons in $^{175}_{71} Lu,$ respectively , are :

A long solenoid of $50\,cm$ length having $100\,turns$ carries a current of $2.5\,A$. The magnetic field at the centre of the solenoid is : $(\mu_o = 4\pi \times 10^{-7} T\,m\,A^{-1})$

The solids which have negative temperature coefficient of resistance are :

The increase in the width of the depletion region in a p-n junction diode is due to :

A ray is incident at an angle of incidence $i$ on one surface of a small angle prism(with angle of prism A) and emerges normally from the opposite surface. If the refractive index of the material of the prism is $\mu$. then the angle of incidence is nearly equal to:

Assume that light of wavelength $600\, nm$ is coming from a star. The limit of resolution of telescope whose objective has a diameter of $2\,m$ is :

A spherical conductor of radius 10 cm has a charge of \(3.2 \times 10^{-7} C\) distributed uniformly. What is the magnitude of electric field at a point \(15\,cm\) from the centre of the sphere?
\((\frac {1}{4\pi \epsilon_o} = 9 \times 10^9 Nm^2/C^2)\)

For transistor action, which of the following statements is correct ?

The color code of a resistance is given below : The values of resistance and tolerance, respectively, are :

In a certain region of space with volume $0.2 \,m^3$, the electric potential is found to be $5\,V$ throughout. The magnitude of electric field in this region is:

A short electric dipole has a dipole moment of \(16 \times 10^{-9} C\, m\). The electric potential due to the dipole at a point at a distance of \(0.6 \,m\) from the centre of the dipole, situated on a line making an angle of \(60\degree\)with the dipole axis is : \((\frac {1}{4\pi \epsilon_o}= 9 \times 10^9 N\,m^2/C^2)\)

A resistance wire connected in the left gap of a metre bridge balances a $10\, \Omega$ resistance in the right gap at a point which divides the bridge wire in the ratio $3 : 2$. If the length of the resistance wire is $1.5\,m$, then the length of 1 $\Omega$ of the resistance wire is:

A wheel with $20$ metallic spokes each $1\, m$ long is rotated with a speed of $120\, rpm$ in a plane perpendicular to a magnetic field of $0.4\, G$. The induced emf between the axle and rim of the wheel will be, $(1 G = 10^{-4}\, T)$

Which of the following graph represents the variation of resistivity $(\rho)$ with temperature (T) for copper ?

A screw gauge has least count of 0.01 mm and there are 50 divisions in its circular scale. The pitch of the screw gauge is:

Dimensions of stress are: