This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
additivity of charges say total charge is equal tbe algebric sum but superposition principle state charge to be vector sum.Why is it so |
| Answer» additivity of charges say total charge is equal tbe algebric sum but superposition principle state charge to be vector sum.Why is it so | |
| 2. |
Two rods A and B of different materials but same cross section are joined as shown in figure. The free end of A is maintained at 100∘C and the free end of B is maintained at 0∘C. If l2=2l1,K1=2K2 and rods are thermally insulated from sides to prevent heat losses, then the temperature θ of the junction of the two rods is |
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Answer» Two rods A and B of different materials but same cross section are joined as shown in figure. The free end of A is maintained at 100∘C and the free end of B is maintained at 0∘C. If l2=2l1,K1=2K2 and rods are thermally insulated from sides to prevent heat losses, then the temperature θ of the junction of the two rods is |
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| 3. |
A prismatic, straight, elastic, cantilever beam is subjected to a linearly distributed transverse load as shown below. If the beam length is L,Young's modulus E and area moment of inertia I, the magnitude of the maximum deflection is |
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Answer» A prismatic, straight, elastic, cantilever beam is subjected to a linearly distributed transverse load as shown below. If the beam length is L,Young's modulus E and area moment of inertia I, the magnitude of the maximum deflection is |
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| 4. |
A simple pendulum of mass m and charge q is hanging from the roof of a car moving on a circular track of. Radius r with a speed v . At equillibrium pendulum string makes angle a with equillibrium . Find magnitude and direction of E required so that the string makes same angle a on other side of vertical |
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Answer» A simple pendulum of mass m and charge q is hanging from the roof of a car moving on a circular track of. Radius r with a speed v . At equillibrium pendulum string makes angle a with equillibrium . Find magnitude and direction of E required so that the string makes same angle a on other side of vertical |
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| 5. |
A parallel plate capacitor with air as medium between the plates has a capacitance of 10μF. The area of capacitor is divided into two equal halves and filled with two media as shown in the figure having dielectric constant k1=2 and k2=4. The capacitance of the system will now be |
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Answer» A parallel plate capacitor with air as medium between the plates has a capacitance of 10μF. The area of capacitor is divided into two equal halves and filled with two media as shown in the figure having dielectric constant k1=2 and k2=4. The capacitance of the system will now be
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| 6. |
If a light ray from air enters three different media in such a way that the refracted angles are 450, 300 and 600 respectively. Identify the right statement with respect to the optical density of these media. |
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Answer» If a light ray from air enters three different media in such a way that the refracted angles are 450, 300 and 600 respectively. Identify the right statement with respect to the optical density of these media. |
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| 7. |
In axial line potential will not be negative?? |
| Answer» In axial line potential will not be negative?? | |
| 8. |
45. What is meant by incident radiation and intensity of incident radiation? |
| Answer» 45. What is meant by incident radiation and intensity of incident radiation? | |
| 9. |
A man walking with a speed of 3m/s passes under a lamp hanging of 8 m above the ground. If the height of the man is 2m,the velocity in m/s with which the edge of the shadow of the man head moves over the ground is. |
| Answer» A man walking with a speed of 3m/s passes under a lamp hanging of 8 m above the ground. If the height of the man is 2m,the velocity in m/s with which the edge of the shadow of the man head moves over the ground is. | |
| 10. |
A compound pendulum has a time period T about a certain point in a vertical plane about a fixed axispassing through the pendulum. The maximum number of point on a vertical line passing throughcentre of mass about which time period will be T is(2) 4(3) 8(4) 6 |
| Answer» A compound pendulum has a time period T about a certain point in a vertical plane about a fixed axispassing through the pendulum. The maximum number of point on a vertical line passing throughcentre of mass about which time period will be T is(2) 4(3) 8(4) 6 | |
| 11. |
Find displacement when velocity is (v+u)÷2 |
| Answer» Find displacement when velocity is (v+u)÷2 | |
| 12. |
A magnetic field set up using Helmholtz coils (described in Exercise4.16) is uniform in a small region and has a magnitude of 0.75 T. Inthe same region, a uniform electrostatic field is maintained in adirection normal to the common axis of the coils. A narrow beam of(single species) charged particles all accelerated through 15 kVenters this region in a direction perpendicular to both the axis ofthe coils and the electrostatic field. If the beam remains undeflectedwhen the electrostatic field is 9.0 × 10–5 V m–1, make a simple guessas to what the beam contains. Why is the answer not unique? |
| Answer» A magnetic field set up using Helmholtz coils (described in Exercise4.16) is uniform in a small region and has a magnitude of 0.75 T. Inthe same region, a uniform electrostatic field is maintained in adirection normal to the common axis of the coils. A narrow beam of(single species) charged particles all accelerated through 15 kVenters this region in a direction perpendicular to both the axis ofthe coils and the electrostatic field. If the beam remains undeflectedwhen the electrostatic field is 9.0 × 10–5 V m–1, make a simple guessas to what the beam contains. Why is the answer not unique? | |
| 13. |
23 A particle of mass m strikes elastically on a wall with velocity v, at an angle of 60 from the wall then magnitude of change in momentum of ball along the wall is |
| Answer» 23 A particle of mass m strikes elastically on a wall with velocity v, at an angle of 60 from the wall then magnitude of change in momentum of ball along the wall is | |
| 14. |
The power radiated by a black body is p and it radiates maximum energy at wavelength λ if the temperature of black body is now changed so that it radiates maximum energy at wavelength 3/4λ the oower radiated by it becomes nPthe value of n is |
| Answer» The power radiated by a black body is p and it radiates maximum energy at wavelength λ if the temperature of black body is now changed so that it radiates maximum energy at wavelength 3/4λ the oower radiated by it becomes nPthe value of n is | |
| 15. |
The unit for molar susceptibility is |
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Answer» The unit for molar susceptibility is |
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| 16. |
A proton and an α−particle enters a uniform magnetic field in a perpendicular direction with the same speed. If the proton takes 25 μs to make 5 revolutions, then the time period for the α−particle will be: |
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Answer» A proton and an α−particle enters a uniform magnetic field in a perpendicular direction with the same speed. If the proton takes 25 μs to make 5 revolutions, then the time period for the α−particle will be: |
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| 17. |
Two similar circular loops of radius R,are lying concentrically with their planes at right angles to each other .The currents flowing in them are (I) and (I\sqrt3) respectively .The magnetic field at yhe centre of the coil is |
| Answer» Two similar circular loops of radius R,are lying concentrically with their planes at right angles to each other .The currents flowing in them are (I) and (I\sqrt3) respectively .The magnetic field at yhe centre of the coil is | |
| 18. |
A cycle can bend upto a maximum angle of 45∘. If the radius of the bend is 10 m, then what should be the maximum speed of the cyclist so that he does not crash? |
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Answer» A cycle can bend upto a maximum angle of 45∘. If the radius of the bend is 10 m, then what should be the maximum speed of the cyclist so that he does not crash? |
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| 19. |
Two blocks each of mass 'm' moving with equal speedv'in opposite directions strike the opposite ends ofmass less spring placed between them. If 'K'is forceconstant of the spring, then the maximum compression-of the spring is : |
| Answer» Two blocks each of mass 'm' moving with equal speedv'in opposite directions strike the opposite ends ofmass less spring placed between them. If 'K'is forceconstant of the spring, then the maximum compression-of the spring is : | |
| 20. |
What is the ratio of the angular velocity of the hour hand of a watch to the angular velocity of Earth's rotation about its axis? |
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Answer» What is the ratio of the angular velocity of the hour hand of a watch to the angular velocity of Earth's rotation about its axis? |
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| 21. |
When a body is projected with velocity →v, horizontally from a height h.Column-IColumn-II(a) The speed of body at any time t is(p) √2ghu2(b) It will strike the ground after time t is equal to (q) √2hg(c) The path followed by the body is expressed as y equal to (r) 12gx2u2(d) The value of tanθ, where θ is the angle made by velocity striking the ground with horizontal is equal to (s) √v2+g2t2 |
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Answer» When a body is projected with velocity →v, horizontally from a height h. |
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| 22. |
A 5 ampere current is passed through a solution of zinc sulphate for 40 minutes. The amount of zinc deposited at the cathode is: |
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Answer» A 5 ampere current is passed through a solution of zinc sulphate for 40 minutes. The amount of zinc deposited at the cathode is: |
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| 23. |
49.An artificial satellite is moving around earth in a circular orbit with speed equal to one fourth of the escape speed of a body from the surface of earth.The height of satellite above earth's surface is(R is radius of earth): |
| Answer» 49.An artificial satellite is moving around earth in a circular orbit with speed equal to one fourth of the escape speed of a body from the surface of earth.The height of satellite above earth's surface is(R is radius of earth): | |
| 24. |
In absorbtion spectra,we pass em radiation thorugh unexited atoms . (a)they absorb some energy, of which corresponding black bands are seen on the photoelectric plate. If they absorb energy from the light, that means the atoms went to an excited state((do all of them absob energy from light?)). so when they would return back to the ground state, they should emit radiation of the same wavelength, if they do why do we see black bands then?(i m talking abt absorbtion spectra) |
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Answer» In absorbtion spectra,we pass em radiation thorugh unexited atoms . (a)they absorb some energy, of which corresponding black bands are seen on the photoelectric plate. If they absorb energy from the light, that means the atoms went to an excited state((do all of them absob energy from light?)). so when they would return back to the ground state, they should emit radiation of the same wavelength, if they do why do we see black bands then?(i m talking abt absorbtion spectra) |
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| 25. |
An AC voltage E=220sin(ωt−π6) is connected across a certain device. The current flowing through this device is i=115 sin(ωt+π3). The correct phasor diagram, of applied voltage and current flowing in the circuit, is, |
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Answer» An AC voltage E=220sin(ωt−π6) is connected across a certain device. The current flowing through this device is i=115 sin(ωt+π3). The correct phasor diagram, of applied voltage and current flowing in the circuit, is, |
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| 26. |
{ 10. An uniform rod of mass }15kg and length }5m} is held stationary with the help of a light string } as shown in figure. The tension in the string is }{(g=10m/s^2) |
| Answer» { 10. An uniform rod of mass }15kg and length }5m} is held stationary with the help of a light string } as shown in figure. The tension in the string is }{(g=10m/s^2) | |
| 27. |
two blocks of mass 2kg and 4kg are hanging with help of massless string passding over an ideal pully inside an elevator .The elevator is moving upword with an acceleration g/2 .the yension in the string connected between the blocks will be ? im unable to unders†an d this problem ,explain briefly |
| Answer» two blocks of mass 2kg and 4kg are hanging with help of massless string passding over an ideal pully inside an elevator .The elevator is moving upword with an acceleration g/2 .the yension in the string connected between the blocks will be ? im unable to unders†an d this problem ,explain briefly | |
| 28. |
An U− tube of base length ′l′ filled with the same volume of two liquids of densities ρ and 2ρ is moving with an acceleration ′a′ on the horizontal plane, as shown in the figure. If the difference in heights of the liquid columns in the two vertical limbs (open to the atmosphere) is zero, then the height h is given by |
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Answer» An U− tube of base length ′l′ filled with the same volume of two liquids of densities ρ and 2ρ is moving with an acceleration ′a′ on the horizontal plane, as shown in the figure. If the difference in heights of the liquid columns in the two vertical limbs (open to the atmosphere) is zero, then the height h is given by |
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| 29. |
A spring having with a spring constant 1200 N m–1is mounted on a horizontal table as shown in Fig. A mass of 3 kg isattached to the free end of the spring. The mass is then pulledsideways to a distance of 2.0 cm and released.Determine (i) the frequency of oscillations, (ii) maximumacceleration of the mass, and (iii) the maximum speed of the mass. |
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Answer» A spring having with a spring constant 1200 N m–1
Determine (i) the frequency of oscillations, (ii) maximum |
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| 30. |
A spherical conductor of radius R carries charge Q on its surface. The value of electric field just outside the surface of the conductor is E. If the radius of the counductor is doubled while keeping the charge same, what will be the value of new electric field just outside the surface of the conductor? |
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Answer» A spherical conductor of radius R carries charge Q on its surface. The value of electric field just outside the surface of the conductor is E. If the radius of the counductor is doubled while keeping the charge same, what will be the value of new electric field just outside the surface of the conductor? |
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| 31. |
A rigid massless beam is balanced by a body of mass 4m on the left hand side and a pulley-mass system on the right hand side. The value of xy is : (Consider the rope and pulley to be massless). |
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Answer» A rigid massless beam is balanced by a body of mass 4m on the left hand side and a pulley-mass system on the right hand side. The value of xy is : |
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| 32. |
An optical fibre communication system works on a wavelength 1.3um.The number of subscribes it can feed if a channel requires 20KHz are |
| Answer» An optical fibre communication system works on a wavelength 1.3um.The number of subscribes it can feed if a channel requires 20KHz are | |
| 33. |
The threshold frequency v0 for a metal is 7.0 X 1014s-1. Calculate the kinetic energy of an electron emitted when radiation of frequency v = 1.0 X 1015 s-1 hits the metal. |
| Answer» The threshold frequency v0 for a metal is 7.0 X 1014s-1. Calculate the kinetic energy of an electron emitted when radiation of frequency v = 1.0 X 1015 s-1 hits the metal. | |
| 34. |
Two identical small bodies each of mass M and charge Q suspended from two strings each of length l from a common fixed point. If whole system is taken into an orbiting artificial satelite , then the strings make an angle θ with each other . The value of θ is |
| Answer» Two identical small bodies each of mass M and charge Q suspended from two strings each of length l from a common fixed point. If whole system is taken into an orbiting artificial satelite , then the strings make an angle θ with each other . The value of θ is | |
| 35. |
The velocity of a particle is V=V0+gt+ft if its position is X=0 at t=0 then it's displacement after unit time t=1 is A) V0 +(g/2) +(f/3) B) V0 +g +f C) V0 + (g/2) + f D) V0 + 2g + 3f |
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Answer» The velocity of a particle is V=V0+gt+ft if its position is X=0 at t=0 then it's displacement after unit time t=1 is A) V0 +(g/2) +(f/3) B) V0 +g +f C) V0 + (g/2) + f D) V0 + 2g + 3f |
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| 36. |
The radius of gyration of a uniform disc about a line perpendicular to the disc equals its radius. Find the distance of the line from the centre. |
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Answer» The radius of gyration of a uniform disc about a line perpendicular to the disc equals its radius. Find the distance of the line from the centre. |
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| 37. |
120.A force F is applied at the center of a disc of mass M. The minimum value of coefficient of friction of the surface for rolling is |
| Answer» 120.A force F is applied at the center of a disc of mass M. The minimum value of coefficient of friction of the surface for rolling is | |
| 38. |
A wire of density ρ is stretched between two clamps a distance L apart, while being subjected to an extension l. Y is the Young's modulus of the material of the wire. The lowest frequency of transverse vibrations of the wire is given by |
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Answer» A wire of density ρ is stretched between two clamps a distance L apart, while being subjected to an extension l. Y is the Young's modulus of the material of the wire. The lowest frequency of transverse vibrations of the wire is given by |
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| 39. |
A capillary tube of radius r is immersed in water and water rises in it to a height h. The mass of water in the capillary tube is 5 g. Another capillary tube of radius 2r is immersed in water. The mass of water that will rise in this tube is: |
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Answer» A capillary tube of radius r is immersed in water and water rises in it to a height h. The mass of water in the capillary tube is 5 g. Another capillary tube of radius 2r is immersed in water. The mass of water that will rise in this tube is: |
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| 40. |
The susceptibility of magnesium at 300 K is 1.2 ×10−5. At what temperature will the susceptibility increase to 1.8 ×10−5 ? |
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Answer» The susceptibility of magnesium at 300 K is 1.2 ×10−5. At what temperature will the susceptibility increase to 1.8 ×10−5 ? |
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| 41. |
the equation of an SHM with amplitude A and angular frequency w in which all the dis†an ces are measured from one extreme position and time is taken to be zero at the other extreme position |
| Answer» the equation of an SHM with amplitude A and angular frequency w in which all the dis†an ces are measured from one extreme position and time is taken to be zero at the other extreme position | |
| 42. |
In the figure, a rod closing the circuit moves along a U−shaped wire at a constant speed v under the action of the force F. The circuit is in a uniform magnetic field perpendicular to its plane. Calculate F, if the rate of generation of heat is P. |
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Answer» In the figure, a rod closing the circuit moves along a U−shaped wire at a constant speed v under the action of the force F. The circuit is in a uniform magnetic field perpendicular to its plane. Calculate F, if the rate of generation of heat is P. |
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| 43. |
In the given figure, a particle of mass 1 kg is projected at t=0. The angle made by the particle with the horizontal after 2 seconds is |
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Answer» In the given figure, a particle of mass 1 kg is projected at t=0. The angle made by the particle with the horizontal after 2 seconds is |
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| 44. |
A coil carries a current and experiences a torque due to a magnetic filed. The value of the torque is 80% of the maximum possible torque. The angle between the magnetic field and the normal to the plane of the coil is |
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Answer» A coil carries a current and experiences a torque due to a magnetic filed. The value of the torque is 80% of the maximum possible torque. The angle between the magnetic field and the normal to the plane of the coil is |
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| 45. |
A ring of mass 0.250 kg and radius 200 cm and another ring of mass 0.500 kg and radius 400 cm have the same center. Find the moment of inertia of the system of two rings about the axis passing through their centers and perpendicular to their plane. |
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Answer» A ring of mass 0.250 kg and radius 200 cm and another ring of mass 0.500 kg and radius 400 cm have the same center. Find the moment of inertia of the system of two rings about the axis passing through their centers and perpendicular to their plane. |
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| 46. |
Thevelocity associated with a proton moving in a potential difference of1000 V is 4.37 × 105ms–1.If the hockey ball of mass 0.1 kg is moving with this velocity,calculate the wavelength associated with this velocity. |
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Answer» The |
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| 47. |
A ball is drawn from a top of height H it covers a distance of x/2 in the last second of its motion . How long does the balll remain in air ? |
| Answer» A ball is drawn from a top of height H it covers a distance of x/2 in the last second of its motion . How long does the balll remain in air ? | |
| 48. |
Maximum sound pressure tolerable by the human ear is 30 N/m2. For sound of frequency 103 Hz and speed 300 m/s, the maximum displacement of particles of medium is [density of air 1.5 kg/m3)] |
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Answer» Maximum sound pressure tolerable by the human ear is 30 N/m2. For sound of frequency 103 Hz and speed 300 m/s, the maximum displacement of particles of medium is |
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| 49. |
the angular momentum of system of particle is conserved when no external force acts upon the system. is this statement true |
| Answer» the angular momentum of system of particle is conserved when no external force acts upon the system. is this statement true | |
| 50. |
A spring has a certain mass suspended from it and its period for vertical oscillation is T. The spring is now cut into two equal halves and the same mass is suspended from one of the halves. The period of vertical oscillation is now |
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Answer» A spring has a certain mass suspended from it and its period for vertical oscillation is T. The spring is now cut into two equal halves and the same mass is suspended from one of the halves. The period of vertical oscillation is now
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