List of top Questions asked in COMEDK UGET

An optical fibre communication system works on a wavelength of \( 1.3 \, \mu m \). The number of subscribers it can feed, if a channel requires 20 kHz, are:
When the expansion of a gas occurs in vacuum and at constant volume, then:
Carbon monoxide is poisonous to human beings because:
For motion under central forces, which quantity will be conserved?
Which of the following statement is incorrect?
If impedance is \( \sqrt{3} \) times resistance, then find phase difference.
A bar magnet is oscillating in the earth’s magnetic field with a period \( T \). What happens to its period and motion, if its mass is quadrupled?
The relative permeability of iron is 6000. Its magnetic susceptibility is
The relative errors in the measurement of two lengths \(1.02 \, \text{cm} \pm 0.01 \, \text{cm}\) and \(9.89 \, \text{cm} \pm 0.01 \, \text{cm}\) is
Ba-122 has half-life of 2 min. Experiment has to be done using Ba-122 and it takes 10 min to set up the experiment. It initially had 80 g of Ba-122. How much Ba-122 was left when the experiment started?
When the speed of light becomes \( \frac{2}{3} \) of its present value, then the energy released in a given atomic explosion would
What should be the value of self-inductance of an inductor that should be connected to 220 V, 50 Hz supply, so that a maximum current of 0.9 A flows through it?
The magnifying power of a telescope is 9. When adjusted for parallel rays, the distance between the objective and eyepiece is 20 cm. The focal lengths of lenses are:
Two masses of 1g and 9g are moving with equal kinetic energy. The ratio of magnitude of their momentum is
When two bodies collide with each other such that their kinetic energy remains constant, their collision is said to be
In a detector, the output circuit consists of \( R = 10 \, \text{k}\Omega \) and \( C = 100 \, \text{pF} \). The frequency of carrier signal it can detect is:
According to Pascal’s law, pressure in a fluid at rest is the same at all points, if
Newton’s second law of rotational motion of a system of particles having angular momentum \( L \) is given by
If an electron in hydrogen atom jumps from an orbit of level \( n = 3 \) to an orbit at level \( n = 2 \), emitted radiation has a frequency of
\( (R = \text{Rydberg’s constant}, \ c = \text{speed of light}) \)
Within the elastic limit, the corresponding stress is known as
A wire is stretched to double of its length. The strain is
Kepler’s second law of planetary motion corresponds to
A constant potential energy of a satellite is given as \[ PE = r \cdot KE \] where PE = potential energy and KE = kinetic energy. The value of \( r \) will be
A long solenoid has 20 turns cm\(^{-1}\). The current necessary to produce a magnetic field of 20 mT inside the solenoid is approximately
The resistance of a wire is \( R \) ohm. If it is melted and stretched to \( n \) times its original length, its new resistance will be