List of top Questions asked in KCET

An unpolarised light of intensity I is passed through two polaroids kept one after the other with their planes parallel to each other. The intensity of light emerging from second polaroid is \(\frac{I}{4}\). The angle between the pass axes of the polaroids is

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

In the Rutherford’s alpha scattering experiment, as the impact parameter increases, the scattering angle of the alpha particle

In an experiment to study photo-electric effect the observed variation of stopping potential with frequency of incident radiation is as shown in the figure. The slope and y-intercept are respectively

For a point object, which of the following always produces virtual image in air?

The ratio of the magnitudes of electric field to the magnetic field of an electromagnetic wave is of the order of

Total impedance of a series LCR circuit varies with angular frequency of the AC source connected to it as shown in the graph. The quality factor Q of the series LCR circuit is

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

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.

An equiconvex lens made of glass of refractive index \(\frac{3}{2}\) has focal length f in air. It is completely immersed in water of refractive index \(\frac{4}{3}\). The percentage change in the focal length is

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

A square loop of side 2 cm enters a magnetic field with a constant speed of 2 cm s^-1 as shown. The front edge enters the field at t = 0s. Which of the following graph correctly depicts the induced emf in the loop?
( Take clockwise direction positive )

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 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

An ideal transfomer has a turns ratio of 10. When the primary is connected to 220V,50Hz ac source, the power output is

In series LCR circuit at resonance, the phase difference between voltage and current 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 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 proton and an alpha-particle moving with the same velocity enter a uniform magnetic field with their velocities perpendicular to the magnetic field. The ratio of radii of their circular paths is

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 torque acting on a magnetic dipole placed in uniform magnetic field is zero, when the angle between the dipole axis and the magnetic field is _____.

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

A wire of resistance R is connected across a cell of emf ε and internal resistance r. The current through the circuit is I. In time t, the work done by the battery to establish the current I is

The four bands of a colour coded resistor are of the colours gray, red, gold and gold. The value of the resistance of the resistor is

The resistance of a carbon resistor is 4.7 kΩ ± 5% . The colour of the third band is