List of top Questions asked in COMEDK UGET- 2025

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

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

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:

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:

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

The mean energy per molecule for a diatomic gas 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?

A block of metal A is connected in series with another block of metal B such that the two metal blocks have the same area of cross sections. The thermal conductivity of metal A is \(K\) and the free end of metal A is at \(80^\circ C\). The temperature of the interface is \(60^\circ C\) and the free end of metal B is at \(20^\circ C\). Assuming the two metals have the same thickness, the conductivity of metal B 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

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:

Two identical conducting balls having positive charges \(q_1\) and \(q_2\) are separated by a distance \(r\). If they are made to touch each other and then separated to the same distance, the force between them will be

If voltage across a bulb rated \(220\,V, 50\,W\) drops by \(5\%\) of its rated value, the percentage of the rated value by which the power would decrease is

A vertical spring of spring constant \(24Nm^{-1}\) is fixed on a table. A ball of mass \(0.5\,kg\) at a height \(2\,m\) above the free upper end of the spring falls vertically on the spring so that the spring is compressed by a distance of \(50\,cm\). The net work done in the process is:

A bomb of mass \(20\,kg\) at rest explodes into two pieces of masses \(12\,kg\) and \(8\,kg\). If the velocity of \(8\,kg\) mass is \(6\,ms^{-1}\), then the kinetic energy of the other mass is:

Two identical conductors of lengths \(l\) and \(3l\) respectively are maintained at the same temperature. They are given potential differences in the ratio \(1:3\). The ratio of their drift velocities is

Two simple harmonic motions are represented by equations \(y_1 = 0.5 \sin [200\pi t + \frac{\pi}{3}]\) and \(y_2 = 0.5 \cos \pi t\). The phase difference of the velocity of particle 1 with respect to the velocity of particle 2 is:

If \(E\) is the amplitude of the electric field of the waves starting from the slits in a double slit experiment and \(\theta\) is the phase difference between the waves reaching a point on the screen, the ratio of the amplitude of the resultant electric field at that point on the screen to the amplitude at one of the slits is

Two coherent waves of intensities \(I_1\) and \(I_2\) pass through a region at the same time in the same direction. The sum of maximum to minimum intensities is

For the charge configuration shown here, which of the following is not true?

A convex lens forms a real image of an object with magnification \(m_1\). The lens is moved towards the object to obtain another real image of magnification \(m_2\). The image distance is increased by \(x\). The focal length of the lens is

A Si and a Ge diode has identical physical dimensions. The band gap in Si is larger than that in Ge. On applying identical reverse bias across these diodes,

A charged particle is released from rest in a region of space in which steady and uniform electric and magnetic fields are parallel to each other. The particle will move in a

Emission of electrons from a metal plate illuminated with monochromatic electromagnetic radiation will always take place provided

A particle starts from rest and moves along the \(x\)-axis with a velocity that varies as \(v = \sqrt{100 + 4x}\,\text{ms}^{-1}\). The acceleration of the particle is: