List of top Physics Questions asked in KCET

A stretched wire of a material whose Young's modulus Y = 2 × 10¹¹ Nm^-2 has Poisson's ratio of 0.25. Its lateral strain ε_l = 10^-3. The elastic energy density of the wire is

A metallic rod of length 1 m held along east-west direction is allowed to fall down freely. Given horizontal component of earth’s magnetic field B_H = 3 × 10^-5 T. The emf induced in the rod at an instant t = 2s after it is released is ( Take g = 10 ms^-2 )

The equivalent resistance between the points A and B in the following circuit is

Ten identical cells each emf 2V and internal resistance 1Ω are connected in series with two cells wrongly connected. A resistor of 10Ω is connected to the combination. What is the current through the resistor?

The current in a coil changes from 2A to 5A in 0.3s. The magnitude of emf induced in the coil is 1.0V. The value of self-inductance of the coil is

A moving coil galvanometer is converted into an ammeter of range 0 to 5mA. The galvanometer resistance is 90Ω and the shunt resistance has a value of 10Ω. If there are 50 divisions in the galvanometer-turnedammeter on either sides of zero, its current sensitivity is

A positively charged particle of mass m is passed through a velocity selector. It moves horizontally rightward without deviation along the line y = \(\frac{2mv}{qB}\) with a speed v. The electric field is vertically downwards and magnetic field is into the plane of the paper. Now, the electric field is switched off at t = 0. The angular momentum of the charged particle about origin O at t = \(\frac{\pi m}{qB}\) is

A uniform electric field vector \(\vec{E}\) exists along horizontal direction as shown. The electric potential at A is V_A . A small point charge q is slowly taken from A to B along the curved path as shown. The potential energy of the charge when it is at point B is

Electric field at a distance ‘r’ from an infinitely long uniformly charged straight conductor, having linear charge density λ is E₁. Another uniformly charged conductor having same linear charge density λ is bent into a semicircle of radius ‘r’. The electric field at its centre is E₂ . Then

In the following equation representing β^- decay, the number of neutrons in the nucleus X is
\(_{83}^{210}\text{Bi}\rightarrow X+e^{-1}+\bar{v}\)

The Curie temperatures of Cobalt and iron are 1400K and 1000K respectively. At T = 1600K , the ratio of magnetic susceptibility of Cobalt to that of iron is

The P-V diagram of a Carnot's engine is shown in the graph below. The engine uses 1 mole of an ideal gas as working substance. From the graph, the area enclosed by the P-V diagram is
[ The heat supplied to the gas is 8000 J ]

For a given pair of transparent media, the critical angle for which colour is maximum?

A point object is moving at a constant speed of 1 ms^-1 along the principal axis of a convex lens of focal length 10cm. The speed of the image is also 1 ms^-1 , when the object is at _______ cm from the optic centre of the lens.

Three energy levels of hydrogen atom and the corresponding wavelength of the emitted radiation due to different electron transition are as shown. Then

A cubical Gaussian surface has side of length a = 10 cm. Electric field lines are parallel to x-axis as shown. The magnitudes of electric fields through surfaces ABCD and EFGH are 6kNC^-1 and 9kNC^-1 respectively. Then the total charge enclosed by the cube is
[Take ε₀ = 9 × 10^-12 Fm^-1]

When a p-n junction diode is in forward bias, which type of charge carriers flows in the connecting wire?

A full-wave rectifer with diodes D₁ and D₂ is used to rectify 50 Hz alternating voltage. The diode D₁ conducts _______ times in one second.

For a given electric current the drift velocity of conduction electrons in a copper wire is v_d and their mobility is μ . When the current is increased at constant temperature

The horizontal component of Earth’s magnetic field at a place is 3 × 10^-5 T. If the dip at that place is 45°, the resultant magnetic field at that place is

The speed of sound in an ideal gas at a given temperature T is v. The rms speed of gas molecules at that temperature is v_rms. The ratio of the velocities v and v_rms for helium and oxygen gases are X and X' respectively. Then \(\frac{X}{X'}\) is equal to

A particle is in uniform circular motion. Related to one complete revolution of the particle, which among the stataments is incorrect ?

When light propagates through a given homogeneous medium, the velocities of

Five capacitors each of value 1 μF are connected as shown in the figure. The equivalent capacitance between A and B is

100 g of ice at 0 °C is mixed with 100 g of water at 100 °C. The final temperature of the mixture is
[Take L_f= 3.36 × 10⁵ J kg^-1 and S_w = 4.2 × 10³ J kg^-1 k-¹]