Quiz: 12th Grade Physics Practice Paper!

50 Questions

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Quiz: 12th Grade Physics Practice Paper!

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Questions and Answers
  • 1. 
    What would be the electric flux due to two charges one at the origin of the Gaussian sphere and another at a distance of 4b from origin. Let the radius of the Gaussian sphere be 3b and the charge be Q.
    • A. 
    • B. 
    • C. 
    • D. 

      0

  • 2. 
    What happens to mutual inductance of pair of coils when distance between the coils is increased:
    • A. 

      Mutual Inductance of first coil will increase with decrease in second coil

    • B. 

      Mutual Inductance of both the coils increases

    • C. 

      Mutual Inductance of both the coils decreases

    • D. 

      Mutual Inductance of second coil will increase with decrease in first coil

  • 3. 
    For a semiconductor a negative resistance could found during a:
    • A. 

      Negative Slope

    • B. 

      Positive Slope

    • C. 

      Constant Slope

    • D. 

      Variable Slope

  • 4. 
    What would be the current through the resistance  which is connected to three voltage source  connected in parallel to each other:
    • A. 
    • B. 
    • C. 
    • D. 
  • 5. 
    What is the reason for the damping of copper plate when it is allowed to oscillate in between the two magnetic poles:
    • A. 

      Polarisation

    • B. 

      Eddy Current

    • C. 

      Amplitude Modulation

    • D. 

      Stationary Waves

  • 6. 
    What is the S.I. Unit of Radioactivity:
    • A. 

      Newton

    • B. 

      Curie

    • C. 

      Becquerel

    • D. 

      Joule

  • 7. 
    Welders wear special goggles to protect their eyes from:
    • A. 

      Ultraviolet Rays

    • B. 

      Infrared Rays

    • C. 

      Microwaves

    • D. 

      Cosmic Rays

  • 8. 
    De Broglie waves associated with a football is not visible because:
    • A. 

      Velocity of the football

    • B. 

      Weight of the football

    • C. 

      Density of the football

    • D. 

      Mass of the football

  • 9. 
    When does a transistor act as a switch:
    • A. 

      Collector current is kept constant

    • B. 

      Collector current is increases

    • C. 

      Collector current is zero

    • D. 

      Collector current decreases

  • 10. 
    What is used to converge the light beam at a single point on the screen during diffraction:
    • A. 

      Polaroid

    • B. 

      Converging Lens

    • C. 

      Diverging Lens

    • D. 

      Prism

  • 11. 
    When a dielectric medium is introduced in between a capacitor, the capacitance:
    • A. 

      Increases

    • B. 

      Decreases

    • C. 

      Constant

    • D. 

      Becomes Negative

  • 12. 
    If the capacitor is being charged by an external ac source with an instantaneous current of I0 cos ωt. The displacement current would be:
    • A. 
    • B. 
    • C. 
    • D. 
  • 13. 
    In which phenomenon the electrons move with an average velocity which is independent of time, although the electrons are accelerated:
    • A. 

      Resistivity

    • B. 

      Photoelectric Effect

    • C. 

      Drift Velocity

    • D. 

      Interference

  • 14. 
    For drift velocity the electrons move from:
    • A. 

      Low potential to high potential

    • B. 

      High potential to low potential

    • C. 

      Negative potential to zero potential

    • D. 

      Positive potential to zero potential

  • 15. 
    A potentiometer is not affected by the internal resistance of the source because:
    • A. 

      The internal resistance of a given cell is fixed

    • B. 

      One of the cells is chosen as a standard cell whose emf is known to a high degree of accuracy

    • C. 

      To maintain a steady current

    • D. 

      It draws no current from the voltage source being measured

  • 16. 
    The air bubble inside water acts as a _____ lens
    • A. 

      Diverging or Concave

    • B. 

      Plane Mirror

    • C. 

      Converging or Convex

    • D. 

      Bi-Convex

  • 17. 
    A+B = Y denotes which Gate:
    • A. 

      NAND Gate

    • B. 

      OR Gate

    • C. 

      NOR Gate

    • D. 

      AND Gate

  • 18. 
    The condition for maximum power dissipation is:
    • A. 
    • B. 
    • C. 
    • D. 
  • 19. 
    What would be the resistance of the light bulb rated at 100 W for 220 V ac supply:
    • A. 

      280 Ω

    • B. 

      465 Ω

    • C. 

      382 Ω

    • D. 

      484 Ω

  • 20. 
    What will happen if an open circuit is used in place of the closed loop?
    • A. 

      Flux is induced at the centre of the circuit

    • B. 

      Flux is induced at only one of the ends of the circuit

    • C. 

      Flux is induced across the open ends of the circuit

    • D. 

      Flux is induced for a short period of time

  • 21. 
    If £ is the emf induced between axle and the rim of a wheel. What is the effect on emf if number of spokes were increased?
    • A. 

      Emf is doubled

    • B. 

      No change in Emf

    • C. 

      Emf becomes half

    • D. 

      Emf becomes 4 times

  • 22. 
    Device used only to check the flow of current in a circuit:
    • A. 

      Voltmeter

    • B. 

      Wheatstone Bridge

    • C. 

      Potentiometer

    • D. 

      Galvanometer

  • 23. 
    Current is flowing from east to west in a wire AB. What would be the direction of the flow of current in a wire CD parallel to AB:
    • A. 

      East to West

    • B. 

      North to South

    • C. 

      West to East

    • D. 

      South to North

  • 24. 
    Name the semiconductor device which works under the reverse bias condition:
    • A. 

      Solar Cell

    • B. 

      Zener Diode

    • C. 

      Transistor

    • D. 

      Microprocessor

  • 25. 
    In a diode, what happens at critical voltage:
    • A. 

      Zener Breakdown

    • B. 

      Saturation Current Flow

    • C. 

      Avalanche Breakdown

    • D. 

      Recombination of Charges Occur

  • 26. 
    Which of the following has a small eyepiece and a large objective lens:
    • A. 

      Telescope

    • B. 

      Compound Microscope

    • C. 

      Simple Microscope

    • D. 

      Periscope

  • 27. 
    What happens below the threshold frequency:
    • A. 

      Partial emission of photoelectrons

    • B. 

      Increase in photoelectric current

    • C. 

      Decrease in photoelectric current

    • D. 

      No emission of photoelectrons

  • 28. 
    What kind of wave are used for line of sight communication:
    • A. 

      Sky Wave

    • B. 

      Sound Wave

    • C. 

      Space Wave

    • D. 

      Light Wave

  • 29. 
    How is the intensity of transmitted light varied when the Polaroid is rotated:
    • A. 

      Intensity doubles

    • B. 

      Intensity becomes half

    • C. 

      Intensity becomes four times

    • D. 

      Intensity remains same

  • 30. 
    Endoscopy is based on the principle of:
    • A. 

      Interference

    • B. 

      Diffraction

    • C. 

      Total Internal Reflection

    • D. 

      Polarisation

  • 31. 
    A charge Q is placed at the centre of the toroid. What will be the current enclosed by the toroid:
    • A. 

      Negative Current

    • B. 

      Zero Current

    • C. 

      Positive Current

    • D. 

      Infinite Current

  • 32. 
    Which of the following will exit the cyclotron first?
    • A. 

      Alpha particle

    • B. 

      Proton

    • C. 

      Deuterium Ion

    • D. 

      Lithium ion

  • 33. 
    Which of the following is vector quantity:
    • A. 

      Current

    • B. 

      Electric Flux

    • C. 

      Electric Potential

    • D. 

      Electric dipole Moment

  • 34. 
    In an equipotential surface:
    • A. 

      Entire charge is concentrated at the centre

    • B. 

      No work is done to bring a test charge to a near charge

    • C. 

      Electric field is in the opposite direction in which the potential decreases

    • D. 

      Electric field due to induced charges opposes the external field within the conductor

  • 35. 
    Which of the following depends on the Inverse Square Law:
    • A. 

      Ampere Circuital Law

    • B. 

      Lenz Law

    • C. 

      Snell’s Law

    • D. 

      Gauss Law

  • 36. 
    Which of the following is dynamically stable in a hydrogen atom:
    • A. 

      Centrifugal Force

    • B. 

      Vander Waal’s Force

    • C. 

      Centripetal Force

    • D. 

      Gravitational Force

  • 37. 
    According to Bohr, what kind of spectrum would be emitted when an accelerating electrons revolves around the  nucleus:
    • A. 

      Line

    • B. 

      Continuous

    • C. 

      Radiation

    • D. 

      Zigzag

  • 38. 
    Which of the following have a high binding energy:
    • A. 

      Iron

    • B. 

      Zinc

    • C. 

      Aluminium

    • D. 

      Uranium

  • 39. 
    The source of energy in sun and stars is:
    • A. 

      Fission

    • B. 

      Photon Energy

    • C. 

      Combustion

    • D. 

      Fusion

  • 40. 
    Neutrino detection is difficult because:
    • A. 

      They have weak interaction with other particles

    • B. 

      They have strong interaction with other particles

    • C. 

      They have nuclear interaction with other particles

    • D. 

      They have ion-ion interaction with other particles

  • 41. 
    Paschen series lies in which region?
    • A. 

      Visible

    • B. 

      Ultraviolet

    • C. 

      Infrared

    • D. 

      Microwave

  • 42. 
    Which of the following have a magnitude but not direction:
    • A. 

      Velocity

    • B. 

      Magnetic Field

    • C. 

      Current

    • D. 

      Force

  • 43. 
    Which of the following will not show polarisation:
    • A. 

      Ultrasonic Wave

    • B. 

      Light Wave

    • C. 

      Micro Wave

    • D. 

      Radio Wave

  • 44. 
    Linearly polarized light only vibrate in:
    • A. 

      Two plane

    • B. 

      One plane

    • C. 

      Four plane

    • D. 

      No plane is involved

  • 45. 
    The S.I. Unit for current sensitivity is:
    • A. 

      Ampere

    • B. 

      Ampere (metre)

    • C. 

      (Ampere)-1

    • D. 

      Ampere (metre)-1

  • 46. 
    The Square Law Device is a:
    • A. 

      Linear Device

    • B. 

      Closed Device

    • C. 

      Non-Linear Device

    • D. 

      Open Device

  • 47. 
    To what phenomenon the decay of light bulb be compared to:
    • A. 

      Radioactive Decay

    • B. 

      Activity Of Sample

    • C. 

      Mean Life

    • D. 

      Electromagnetic Radiation

  • 48. 
    The angle between the true geographic north and the magnetic north is called:
    • A. 

      Magnetic declination

    • B. 

      Angle of dip

    • C. 

      Dynamo Effect

    • D. 

      Gyro-magnetic angle

  • 49. 
    The galvanometer do not show any deflection if:
    • A. 

      Bridge current flow to be constant

    • B. 

      Bridge voltage to be constant

    • C. 

      Bridge is balanced

    • D. 

      Bridge resistance is constant

  • 50. 
    Which of the following is based on conservation of charge:
    • A. 

      Kirchhoff’s Junction Rule

    • B. 

      Kirchhoff’s Voltage Law

    • C. 

      Ohm’s Law

    • D. 

      Biot-Savart Law