List of top Questions asked in COMEDK UGET- 2025

The terms of an infinitely decreasing geometric progression in which all the terms are positive, the first term is 4, and the difference between third and fifth term is \( \frac{32}{81} \), then which of the following is not true?

Which of the following statement is wrong regarding the photo electric effect.

By connecting two given capacitors, a technician was able to make two new capacitors having the effective capacitance \( 12.5\mu F \) and \( 2\mu F \). What would be the capacitance of the given capacitors?

For a short magnet, the magnetic field on the axial line at a distance 10 cm from its centre is \( 1.6 \times 10^{-7} \, T \). What is the magnetic field on its equatorial line at the same distance 10 cm from its centre?

What is the kinetic energy of the electron in the \( n \)th level, moving in a plane under the influence of a magnetic field \( B \)? \([ m\text{ - mass of electron},\; h\text{ - Planck's constant},\; e\text{ - electronic charge}]\)

A rectangular coil of length 10 cm and breadth 9 cm carries a current of 10 A. A long straight conductor carrying a current of 20 A is placed 1 cm from the coil parallel to its length and in the same plane of the coil. What will be the net force acting on the straight conductor?

What should be the value of the inductance of the coil which is to be connected to \( 220 \, V, 50 \, Hz \) supply so that maximum current of \( 3\sqrt{2} \, A \) flows through the circuit?

A monochromatic light of wavelength \( 6000 \, \mathring{A} \) is passed through two media A and B of thickness 10 cm and 16 cm respectively. The number of waves in A is \( \frac{1}{2} \) that of B. If the refractive index of A is \( \frac{4}{3} \), find the refractive index of B.

What is the maximum wavelength of EM radiation required to move an electron from the valence band to conduction band of a semiconductor? [Given: Energy gap \( E_g = 1.98 \times 10^{-19} \, J \); Planck's constant \( h = 6.6 \times 10^{-34} \, Js \)]

In the Young's double slit experiment, when a monochromatic light is used, fringe width obtained is 1 mm. If the wavelength is halved and the slit width is doubled, what will be the new fringe width?

Two wires A and B made of same material having length 10 cm and 40 cm respectively are connected in parallel to the same source of emf 10 V. What will be the ratio of the drift velocity of the electrons in the wire A to the drift velocity in the wire B?

When a metallic spherical shell of radius 20 cm is charged, the potential on its surface is found to be 5 V. The potential at a point 10 cm from the centre of the spherical shell is:

An EM wave of frequency \( 5 \times 10^9 \, Hz \) falls normally on a rectangular slit of width \( 3 \, cm \). What is the total angular width of the central maxima?

In the expression \( P = E l^2 m^{-5} G^{-2} \) where \( E, l, m \) and \( G \) represent Energy, Angular Momentum, Mass and Gravitational Constant, the dimensions of \( P \) are

The separation between C and O atoms in CO is \( 0.12 \, nm \). The distance of C atom from the centre of mass is

Across the \( 220 \, V \) source of internal resistance \( 20\Omega \), how many lamps of \( 40 \, W, 100 \, V \) can be connected in parallel so that all the lamps may glow with full brightness.

de Broglie wave length associated with an electron accelerated through a potential difference \( V \) is \( \lambda \). If the accelerating potential is halved, what will be the new wavelength associated with the charged particle?

An open pipe is in second harmonic with frequency \( f_1 \). One end of the tube is closed and frequency is increased to \( f_2 \) and it resonates again with nth harmonic. For what value of \( n \), the ratio of \( \frac{f_1}{f_2} \) is \( \frac{4}{5} \)?

In which of the following circuit do we find the current and voltage in phase?

When a dielectric slab of dielectric constant \( k = 2 \) is used to fill the space between the plates of a parallel plate capacitor, the capacitance of the capacitor is found to be \( 20 \mu F \). What will be the capacitance when the slab is replaced with air?

The focal lengths of the objective and eyepiece of a compound microscope are \( 1 \, \text{cm} \) and \( 10 \, \text{cm} \) respectively. Length of the tube is \( 25 \, \text{cm} \). If the final image is formed at infinity, the magnifying power of the microscope is:

The resistance of the conductor is \( \sqrt{3}\Omega \) the angle made by the V-I graph with the voltage axis is \( \theta \)

A body weighing 125 kg just slides down a rough inclined plane that rises 1 m in every 2 m. What is the coefficient of friction?

If the radius of earth were to shrink by two percent, its mass remaining the same, the acceleration due to gravity on the earth's surface would

A ray of light is travelling from glass of refractive index \( \frac{3}{2} \) to water of refractive index \( \frac{4}{3} \). What is the minimum angle of incidence for which no light enters into the water?