List of top Questions asked in COMEDK UGET- 2025

The ratio of specific heat capacities at constant pressure to that at constant volume for a given mass of a gas is \(\frac{5}{2}\). If the percentage increase in volume of the gas while undergoing an adiabatic change is \(\frac{3}{2}\), then the percentage decrease in pressure will be:

A force of \(-F\hat{i}\) acts at the origin of the coordinate system. The torque about the point \((0,1,-1)\) is:

The EMF of the cell \(Al/Al^{3+}(0.01M) \parallel Fe^{2}+(0.02M)/Fe\) is 1.209 V. The EMF of the cell can be increased by

For a given reaction of the type \( \frac{3}{5}X(aq) \rightarrow \frac{1}{2}Y(aq) + Z(g) \), the correct expression for the rate of disappearance of \(X\) with reference to \(Y\) is}

Which of the following is not true for a perfect conductor?

A cylindrical tank \(0.5\,m\) in radius, rests on a platform \(1.5\,m\) high. Initially the tank is filled with water to a height of \(2.5\,m\). A small plug whose area is \(10^{-4}\,m^2\) is removed from an orifice located on the side of the tank at the bottom. The speed with which the water strikes the ground is: [Assume \(g = 10\,ms^{-2}\)]

A long solenoid has \(400\) turns. When a current of \(100\,A\) is passed through it, the resulting magnetic flux linked with each turn of the solenoid is \(4\,mWb\). The self-inductance of the solenoid is

A bar magnet is oscillating in the earth's magnetic field with a period \(T\). When the length of the bar magnet is doubled and its mass is quadrupled, the time period is \(T_1\). The ratio of \(T_1\) to \(T\) is

Young's modulus of the material of wires X and Y are in the ratio \(4:1\) and the areas of cross sections of the wires X and Y are in the ratio \(2:1\). If the same amount of load is applied to both the wires, the ratio of elongation produced in the wires X and Y will be: (Assume length of the wires X and Y initially are the same)

A sample of an ideal gas is taken through the cyclic process ABCA as shown in figure below. It absorbs \(60\,J\) of heat during the part AB and rejects \(80\,J\) of heat during CA. There is no heat exchanged during the process BC. A work of \(40\,J\) is done on the gas during the part BC. If the internal energy of the gas at A is \(1450\,J\), then the work done by the gas during the part CA is:

The electric and magnetic fields associated with an electromagnetic wave propagating along \(+z\) axis, can be represented by

In a nuclear fusion reaction, two nuclei \(A\) and \(B\) fuse to produce a nucleus \(C\), releasing an amount of energy \(\Delta E\) in the process. If the mass defects of the three nuclei are \(\Delta M_A\), \(\Delta M_B\) and \(\Delta M_C\) respectively, then which of the following relations is true? ( \(c\) is the speed of light)

In the energy band diagram of a material shown below, open circles and filled circles denote holes and electrons respectively. The material is a

A particle moves towards west with a velocity of \(10\,ms^{-1}\). After \(10\,s\) its direction changes towards south and it moves with the same velocity. The average acceleration of the particle is:

The electrical conductivity of a semiconductor increases when electromagnetic radiation of wavelength shorter than \(1.24\,\mu m\) is incident on it. The band gap (in eV) for the semiconductor is

A planet is 121 times heavier than moon and has a diameter 9 times that of moon. If the escape velocity on the planet is \(v\), then the escape velocity on the moon will be:

An LCR series ac circuit is at resonance with \(10\,V\) each across \(L\), \(C\) and \(R\). If the resistance is halved, the respective voltage across \(R\), \(C\) and \(L\) are

Which, of the following is true of the Balmer series of the hydrogen spectrum?
a. The series is in the visible region.
b. The entire series falls in the ultraviolet region
c. The entire series falls in the infrared region
d. The series is partly in the visible region and partly in the infrared region

From a circular disc of radius \(2R\), a smaller circular disc is cut with radius of the larger disc as its diameter. The centre of the hole is at a distance of \(R\) from the centre of the original disc. The distance of the centre of mass of the remaining portion from the centre is:

If the binding energy per nucleon in \( ^7_3Li \) and \( ^4_2He \) nuclei are respectively \(5.60\,MeV\) and \(7.06\,MeV\), then energy of \(p\) in the reaction \( p + ^7_3Li \rightarrow 2\,^4_2He \) is

A sonometer string vibrates with a frequency of \(400\,Hz\). When the length of the string is halved and the tension is altered, it begins to vibrate with a frequency of \(200\,Hz\). The ratio of the new tension to the original tension in the string is:

The radius of earth is \(R\) and acceleration due to gravity on its surface is \(g\). The height at which the acceleration due to gravity becomes \(\frac{g}{8}\) is:

In an experiment to measure the density of the material of a sphere, an error of \(2\%\) occurred while measuring the radius of a sphere and an error of \(3\%\) occurred while measuring the mass of the sphere. What is the maximum percentage error in the measurement of density?

The mean energy per molecule for a diatomic gas is:

The resistance of a wire is \(5\,ohm\) at \(25^\circ C\) and \(7\,ohm\) at \(100^\circ C\). The resistance of the wire at \(0^\circ C\) is