List of top Physics Questions asked in MHT CET

A mass \(m\) suspended from a spring stretches it by \(5\,\text{cm}\) when on the surface of the earth. The mass is then taken to a height of \(1600\,\text{km}\) above earth’s surface and again suspended from the same spring. At this altitude the extension of the spring is (Radius of earth \(= 6400\,\text{km}\))

If \(\lambda_1\) and \(\lambda_2\) are the wavelengths of the first spectral line of the Lyman and Paschen series respectively, then \(\lambda_1 : \lambda_2\) is

A solenoid having \(250\) turns per metre has a core of a material with relative permeability \(500\). What is the approximate value of the magnetisation of the core material, if a current of \(2\,\text{A}\) is passed through it?

A string of length \(L\) and linear density \(m\) has a fundamental frequency \(n\) when stretched by tension \(T\). The fundamental frequency of another string having double the length and double linear density, when the same tension is applied, is

If \(\vec{A} = a_1 \hat{i} + a_2 \hat{j} + a_3 \hat{k}\), then \(\hat{i} \times (\hat{i} \times \vec{A})\) is

The period of oscillation of a mass \(M\) suspended from a spring of negligible mass is \(T\). If along with it another mass \(M\) is also suspended, the period of oscillation now will be

A plano-convex lens is made from glass of refractive index \(1.5\). The radius of curvature of its curved surface is \(R\). Its focal length is

When an alternating emf is applied across a capacitor \(C\), the graph of capacitive reactance \((X_C)\) with frequency \((f)\) of the source of alternating signal is

Assuming the earth to be a sphere of uniform density, the ratio of acceleration due to gravity on the earth's surface to its value at halfway towards the centre of the earth, will be

The Young's double-slit experiment is performed with the light of blue colour \((\lambda_b = 4350\,\text{\AA})\) and then with green colour \((\lambda_g = 5450\,\text{\AA})\). Without changing the experimental setup, if the distance of the sixth fringe from the centre is determined for both the colours as \(x_{\text{blue}}\) and \(x_{\text{green}}\), then \(x_{\text{blue}} : x_{\text{green}}\) is nearly

A proton moving in a perpendicular magnetic field possesses energy \(E\). The magnetic field is increased four times, but the proton is constrained to move in the path of same radius. The kinetic energy will increase

Water rises in a capillary tube to a certain height such that the upward force due to surface tension is balanced by \(63 \times 10^{-4}\,\text{N}\) force due to the weight of the water. The surface tension of water is \(7 \times 10^{-2}\,\text{N m}^{-1}\). The inner diameter of the capillary tube is nearly \((\pi = 22/7)\)

The moment of inertia of a ring about an axis passing through its centre and perpendicular to its plane is \(I\). It is rotating with angular velocity \(\omega\). Another identical ring is gently placed on it so that their centres coincide. If both the rings rotate about the same axis, then loss in kinetic energy is

A stone of mass \(2\,\text{kg}\) attached at one end of a \(2\,\text{m}\) long string is whirled in a horizontal circle. The string makes an angle of \(45^\circ\) with the vertical. Then the centripetal force acting on the stone is (\(g = 10\,\text{m s}^{-2}\), \(\tan 45^\circ = 1\))

A particle of mass \(m\) is rotating in a circle of radius \(r\) having angular momentum \(L\). Then the centripetal force will be

If \(|\vec{A}_1| = 3\), \(|\vec{A}_2| = 4\) and \(|\vec{A}_1 + \vec{A}_2| = 4\), the value of \((2\vec{A}_1 + \vec{A}_2)\cdot(\vec{A}_1 - \vec{A}_2)\) is

A force \(F = (10 + 0.5x)\) N acts on a particle in the x-direction. The work done by the force in displacing the particle from \(x = 0\) to \(x = 2\) m is

The effective length of a magnet is \(31.4\) cm and its pole strength is \(0.8\) A m. The magnetic moment, if it is bent in the form of a semicircle, is

The mutual inductance between two coplanar concentric rings A and B of radii \(R_1\) and \(R_2\) placed in air when a current \(I\) flows through ring A is (\(R_1 \gg R_2\)). (\(\mu_0\) = permeability of free space)

For a transistor \( \dfrac{1}{\alpha_{dc}} - \dfrac{1}{\beta_{dc}} \) is (\(\alpha_{dc}\) and \(\beta_{dc}\) are current gains)

For the following combination of logic gates, when all the three inputs are first high and then low, the output \(Y\) will respectively be

When a ray of light is incident normally on one refracting surface of an equilateral prism of refractive index \(1.5\), the emerging ray \([\sin^{-1}(1/1.5)=41.8^\circ]\)

Capacitors of capacitances \(C_1, C_2\) and \(C_3\) are connected in series. If the combination is connected to a supply of \(V\) volt, the potential difference across capacitor \(C_1\) is

Light of wavelength \(\lambda\) strikes a photoelectric surface and electrons are ejected with energy \(E\). If the wavelength is changed to \(\lambda'\), the energy becomes twice the original value. Which one of the following relations is true for \(\lambda\) and \(\lambda'\)?

A sonometer wire of length \(l_1\) is in resonance with a frequency 250 Hz. If the length of wire is increased to \(l_2\), then 2 beats per second are heard. The ratio of lengths \( \dfrac{l_1}{l_2} \) of wire will be