KCET unofficial answer key for Physics has been released along with questions. Students can check the unofficial KCET physics exam solutions in the following table.
Latest on April 18, 2024:
KCET 2024 Physics Questions and Answers
It contains direct questions and answers of all the sets as all sets had same questions with just shuffling of nubers.
| S.No | Questions | Answers |
|---|---|---|
| 1 | The ratio of molar specific heats of oxygen is | (A) 1.4 |
| 2 | For a particle executing simple harmonic motion (SHM), at its mean position | (B) Velocity is maximum and acceleration is zero |
| 3 | A motor-cyclist moving towards a huge cliff with a speed of 18 kmh-1, blows a horn of source frequency 325 Hz. If the speed of the sound in air is 330 ms-1, the number of beats heard by him is | (A) 5 |
| 4 | A body has a charge of 3.2 C . The number of excess electrons it has is | (C) 2 X 1013 |
| 5 | A point charge A of + 10 C and another point charge B of + 20 C are kept 1m apart in free space. The electrostatic force on A due to B is F1 and the electrostatic force on B due to A is F2 . Then | (B) |
| 6 | A uniform electric field E = 3 x 105NC-1 is acting along the positive Y-axis. The electric flux through a rectangle of area 10cm 30cm whose plane is parallel to the Z-X plane is | (B) 9 X 103 Vm |
| 7 | The total electric flux through a closed spherical surface of radius ‘r’ enclosing an electric dipole of dipole moment 2aq is…… | (A) |
| 8 | Under electrostatic condition of a charged conductor, which among the following statements is true? | (C) Any excess charge resides on the surface of the conductor |
| 9 | A cube of side 1 cm contains 100 molecules each having an induced dipole moment of 6 0.2 10 C m in an external electric field of 1 4NC . The electric susceptibility of the materials is_____ | (B) 5 |
| 10 | A capacitor of capacitance 5 F is charged by a battery of emf 10V. At an instant of time, the potential difference across the capacitors is 4V and the time rate of change of potential difference across the capacitor is 0.6 1 Vs. Then the time rate at which energy is stored the capacitor at the instant is | (A) |
| 11 | E is the electric field inside a conductor whose material has conductivity and resistivity. The current density inside the conductor is j . The correct form of Ohm’s law is | (C) |
| 12 | In the circuit shown, the end A is at potential V0 and end B is grounded. The electric current I indicated in the circuit is | (D) Vo/3R |
| 13 | The electric current flowing through a given conductor varies with time as shown in the graph below. The number of free electrons which flow through a given cross-section of the conductor……….. | (A) 3.125 x 1019 |
| 14 | The I-V graph for a conductor at two different temperatures 100 C and 400 C is as shown in the figure. The temperature coefficient of resistance of the conductor is about (in per degree Celsius) | (A) 3 x 10-3 |
| 15 | An electric blub of 60 W, 120 V is to be connected to 220 V source. What resistance should be connected in series with the bulb, so that the bulb glows properly | (C) 200 ohms |
| 16 | In an experiment to determine the temperature coefficient of resistance of a conductor, a coil of wire X is immersed in a liquid. It is heated by an external agent. A meter bridge set up is used to determine resistance of the coil X at different temperatures. The balancing points | (C) 0.0050 C-1 |
| 17 | A moving electron produces | (B) both electric and magnetic field |
| 18 | A coil having 9 turns carrying a current produces magnetic filed B1 at the centre. Now the coil is rewounded into 3 turns carrying same current. Then the magnetic field at the centre B2 | (A) B1/9 |
| 19 | A particle of specific charge q/m = pie C kg is projected the origin towards positive x-axis with the velocity 1 10ms in a uniform magnetic field B 2kT . The velocity v of particle after time 1 t s 12 will be ( 1 in ms ) | (D) |
| 21 | The magnetic field at the centre of a circular coil of radius R carrying current I is 64 times the magnetic field at a distance x on its axis from the centre of the coil. Then the value of x is | (D) |
| 22 | Magnetic hysterisis is exhibited by ________ magnetic materials. | (C) only ferro |
| 23 | Magnetic susceptibility of Mg at 300 K is 5 1.2 10 . What is its susceptibility at 200 K ? | (C) |
| 24 | A uniform magnetic field of strength B 2mT exists vertically downwards. These magnetic field lines pass through a closed surface as shown in the figure. The closed surface consists of a hemisphere S1 , a right circular cone S2 and a circular surface S3 . The magnetic flux through S1 and S2 are respectively | (A) |
| 25 | In the figure, a conducting ring of certain resistance is falling towards a current carrying straight long conductor. The ring and conductor are in the same plane. Then the | (C) induced electric current is clockwise |
| 26 | An induced current of 2 A flows through a coil. The resistance of the coil is 10Ω. What is the change in magnetic flux associated with the coil in 1 ms ? | (B) |
| 27 | A square loop of side length ‘a ‘ is moving away from an infinitely long current carrying conductor at a constant speed ‘ v ‘ as shown. Let ‘ x ‘ be the instantaneous distance between the long conductor and side AB . The mutual inductance (M) of the square loop – long conductor pair changes with time according to which of the following graphs? | (C) |
| 28 | Which of the following combinations should be selected for better tuning of an LCR circuit used for communication? | (D) |
| 29 | In an LCR series circuit, the value of only capacitance C is varied. The resulting variation of resonance frequency 0f as a function of C can be represented as | (C) |
| 30 | The figure shows variation of R,XL and XC with frequency ‘ f ‘ in a series LCR circuit. Then for what frequency point is the circuit capacitive? | (C) |
| 31 | Electromagnetic waves are incident normally on a perfectly reflecting surface having surface area A. If I is the intensity of the incident electromagnetic radiation and c is the speed of light in vacuum, the force exerted by the electromagnetic wave on the reflecting surface is | (A) 2IA/c |
| 32 | The final image formed by an astronomical telescope is | (D) virtual, inverted and magnified |
| 33 | If the angle of minimum deviation is equal to angle of a prism for an equilateral prism, then the speed of light inside the prism is | (C) |
| 34 | A luminous point object O is placed at a distance 2R from the spherical boundary separating two transparent media of refractive indices n1 and n2 as shown, where R is the radius of curvature of the spherical surface…… | (A) 30 cm in the rarer medium |
| 35 | An equiconvex lens of radius of curvature 14 cm is made up of two different materials. Left half and right half of vertical portion is made up of material of refractive index 1.5……… | (D) 40 cm |
| 36 | A galaxy is moving away from the Earth so that a spectral line at 600 nm is observed at 601 nm . Then the speed of the galaxy with respect to the Earth is | (A) |
| 37 | Three polaroid sheets are co-axially placed as indicated in the diagram. Pass axes of the polaroids 2 and 3 make 30 and 90 with pass axis of polaroid sheet 1. | (B) |
| 38 | In Young’s double slit experiment, an electron beam is used to produce interference fringes of width 1 . Now the electron beam is replaced by a beam of protons with the same experimental set-up and same speed……. | (D) |
| 39 | Light of energy E falls normally on a metal of work function E 3 . The kinetic energies K of the photo electrons are | (C) |
| 40 | The photoelectric work function for photo metal is 2 4eV . Among the four wavelengths, the wavelength of light for which photoemission does not take place is | (C) 700 nm |
| 41 | In alpha particle scattering experiment, if v is the initial velocity of the particle, then the distance of closest approach is d. If the velocity is doubled, then the distance of closest approach becomes | (D) |
| 42 | The ratio of area of first excited state to ground state of orbit of hydrogen atom is | (D) |
| 43 | The ratio of volume of 27 Al nucleus to its surface area is 15 Given R 1.2 10 m | (D) |
| 44 | The natural logarithm of the activity R of a radioactive sample varies with time t as shown. At t=0, there are N0 undecayed nuclei. | (C) |
| 45 | Depletion region in an unbiased semiconductor diode is a region consisting of | (B) |
| 46 | The upper level of valence band and lower level of conduction band overlap in the case of | (B) |
| 47 | In the diagram shown, the Zener diode has a reverse breakdown voltage of VZ . The current through the load resistance R is……. | (D) |
| 48 | A p -n junction diode is connected to a battery of emf 5.7 V in series with a resistant 5k such that it is forward biased. If the barrier potential of the diode is 0.7 V, neglecting the diode resistance, the current in the circuit is | (B) |
| 49 | An athlete runs along a circular track of diameter 80m. The distance travelled and the magnitude of displacement of the athlete | (A) |
| 50 | Among the given pair of vectors, the resultant of two vectors can never be 3 units. The vectors are | (D) |
| 51 | A block of certain mass is placed on a rough inclined plane. The angle between the plane and the horizontal is 300. The coefficients of static and kinetic frictions between the block and the inclined plane are 0.6 and 0.5 | (B) |
| 52 | A particle of mass 500 g is at rest. It is free to move along a straight line. The power delivered to the particle varies with time according to the following graph | (C) |
| 53 | Dimensional formula for activity of a radioactive substance is | (C) |
| 54 | A ceiling fan is rotating around a fixed axle as shown. The direction of angular velocity is along | (D) |
| 55 | A body of mass 1 kg is suspended by a weightless string which passes over a frictionless pulley of mass 2 kg as shown in the figure. The mass is released from a height of 1.6m from the ground | (B) |
| 56 | What is the value of acceleration due to gravity at a height equal to half the radius of the Earth, from its surface ? | (A) |
| 57 | A thick metal wire of density and length ‘L’ is hung from a rigid support. The increase in length of the wire due to its own weight is | (B) |
| 58 | Water flows through a horizontal pipe of varying cross-section at a rate of 0.314 m3s-1. The velocity of water at a point where the radius of the pipe is 10 cm is | (C) |
| 59 | A solid cube of mass m at a temperature 0 is heated at a constant rate. It becomes liquid at temperature 1 and vapour at temperature 2 . Let s1 and s2 be specific heats in its solid and | (C) |
| 60 | One mole of an ideal monoatomic gas is taken round the cyclic process MNOM. The work done by the gas is | (D) |