COMEDK 2023 Evening Shift

In an adiabatic expansion of air, the volume is increased by \(6.2 \%\). The percentage change in pressure is \((\gamma=1.4)\)

If the ratio of specific heat of a gas at constant pressure to that at constant volume is \(\gamma\), the change in internal energy of a mass of a gas when the volume changes from \(\mathrm{V}\) to \(3 \mathrm{~V}\) at constant pressure is

The molecules of a given mass of a gas have root mean square speed of \(120 \mathrm{~m} / \mathrm{s}\) at \(88^{\circ} \mathrm{C}\) and 1 atmospheric pressure. The root mean square speed of the molecules at \(127^{\circ} \mathrm{C}\) and 2 ...

Two black bodies \(\mathrm{P}\) and \(\mathrm{Q}\) have equal surface areas and are kept at temperatures \(127^{\circ} \mathrm{C}\) and \(27^{\circ} \mathrm{C}\) respectively. The ratio of thermal power radiated by A to that by B is

If the resultant of all external forces acting on a system of particles is zero, then from an inertial frame one can surely say that

A hockey player hits the ball at an angle of \(37^{\circ}\) from the horizontal with an initial speed of \(40 \mathrm{~m} / \mathrm{s}\) (a right angled triangle with one of the angle is \(37^{\circ}\) and their sides in the ratio of $$6: 8...

\(\mathrm{F}_{\mathrm{A}}, \mathrm{F}_{\mathrm{B}}\) and \(\mathrm{F}_{\mathrm{C}}\) are three forces acting at point \(\mathrm{P}\) as shown in figure. The whole system is in equilibrium state. The magnitude of \(\mathrm{F}_{\mathrm{A}}\) ...

The magnetic permeability '\(\mu\)' a of a paramagnetic substance is :

Find the pole strength of a magnet of length \(2 \mathrm{~cm}\), if the magnetic field strength $B$ at distance \(10 \mathrm{~cm}\) from the centre of a magnet on the axial line of the magnet is \(10^{-4} \mathrm{~T}\).

The nucleus of a helium atom travels along the inside of a straight hollow tube \(4 \mathrm{~m}\) long which forms part of a particle accelerator. If one assumes uniform acceleration, how long is the particle in the tube if it enters at a s...

A drone is flying due west, a little above the train, with a speed of \(10 \mathrm{~m} / \mathrm{s}\). A 270 meter long train is moving due east at a speed of \(20 \mathrm{~m} / \mathrm{s}\). The time taken by the drone to cross the train i...

A magnetic field does not interact with:

A metallic rod of \(10 \mathrm{~cm}\) is rotated with a frequency 100 revolution per second about an axis perpendicular to its length and passing through its one end in uniform transverse magnetic field of strength \(1 \mathrm{~T}\). The em...

The radius of the current carrying circular coil is doubled keeping the current passing through it the same. Then the ratio of the magnetic field produced at the centre of the coil before the doubling of the radius to the magnetic field aft...

A circular loop of area \(0.04 \mathrm{~m}^2\) carrying a current of \(10 \mathrm{~A}\) is held with its plane perpendicular to a magnetic field induction \(0.4 \mathrm{~T}\) Then the torque acting on the circular loop is :

The critical angle of a medium having the refractive index \(\sqrt2\) is :

When angle of incidence on one face of the equilateral glass prism is \(3 / 4^{\text {th }}\) of the angle of prism, the ray of light undergoes minimum deviation. If the velocity of light in vacuum is '\(c\)' then the velocity of light in t...

A person has a normal near point \(25 \mathrm{~cm}\). What is the magnifying power of the simple microscope he used, if the focal length of the convex lens used is \(10 \mathrm{~cm}\) and the final image is formed at the least distance of d...

A lens of power \(+1 \mathrm{D}\) is made in contact with another lens of power \(-2 \mathrm{D}\) the combination will then act as a:

What will be change in wave length, if a light of wave length \(600 \mathrm{~nm}\) travels from air enters a medium of refractive index 1.5 and continues its journey through that medium?

A wheel is free to rotate about a horizontal axis through O. A force of \(200 \mathrm{~N}\) is applied at a point \(\mathrm{P} 2 \mathrm{~cm}\) from the center \(\mathrm{O}\). OP makes an angle of \(55^{\circ}\) with \(\mathrm{x}\) axis and...

The energy gap between valance band and the conduction band for a given material is \(6 \mathrm{~eV}\), then the material is :

The reverse current in the semiconductor diode changes from \(20 \mu \mathrm{A}\) to \(40 \mu \mathrm{A}\) when the reverse potential is changed from \(10 \mathrm{~V}\) to \(15 \mathrm{~V}\), then the reverse resistance of the junction diod...

In the given circuit the diode \(D_1\) and \(D_2\) have the forward resistance \(25 \Omega\) and infinite backward resistance. When they are connected to the source as shown, the current passing through the \(175 \Omega\) resistor is:

The time dependence of a physical quantity P is give by \(\mathrm{P=P}_0 \exp \left(-\alpha t^2\right)\) where \(\alpha\) is a constant and \(t\) is time. The constant \(\alpha\) will

A tentative explanation of observations without assuming that it is true is called

In the young's double slit experiment the fringe width of the interference pattern is found to be \(3.2 \times 10^{-4} \mathrm{~m}\), when the light of wave length \(6400^{\circ} \mathrm{A}\) is used. What will be change in fringe width if ...

A light having wavelength \(6400^{\circ} \mathrm{A}\) is incident normally on a slit of width \(2 \mathrm{~mm}\). Then the linear width of the central maximum on the screen kept \(2 \mathrm{~m}\) from the slit is :

Two open organ pipes A and B of length \(22 \mathrm{~cm}\) and \(22.5 \mathrm{~cm}\) respectively produce 2 beats per sec when sounded together. The frequency of the shorter pipe is

If reaction is \(\mathrm{R}\) and coefficient of friction is \(\mu\), what is work done against friction in moving a body by distance \(\mathrm{d}\) ?