Prasar Bharti (All India Radio) Examination : Previous Year Solved Papers

Prasar Bharti (All India Radio) Examination 2011

Solved Question Paper with Answer

1. Which one of the following physical quantities, is not defined in the terms of force per unit area:

• pressure
• strain
• stress
• Young’s modulus

2. The distance moved by a moving body is equal to:

• area between the distance-time graph and distance axis
• area between the speed-time graph and time axis
• area between the distance-time graph and time axis
• area between the speed-time graph and distance axis.

3. A beaker containing water weighs 100 gm. It is placed on the pan of a balance and a piece of metal weighing 70 gm. and having a volume of 10cc. is placed inside the water in the beaker. The weight of the beaker and the metal would be :

• 170gm.
• 100gm.
• 160gm.
• 30gm.

4. For the same kinetic energy, the momentum shall be maximum for:

• electron
• proton
• deuteron
• alpha particle

5. The common balance works on the principle of equality of:

• forces
• moments of forces
• masses
• masses of pans

6. A particle moves in a circle of radius R with a constant speed under a centripetal force F. The work done in completing a full circle is:

• 2RF
• ?R2F
• 2?RF
• Zero

7. When two quantities are plotted on the graph paper against each other and the result so obtained is a st. line, then

• Both the quantities are equal
• The quantities are inversely proportional to each other
• Sum of both is zero
• The quantities are proportional to each other

8. What is the order of magnitude of 260°?

• 103
• 104
• 102
• 10

9. The maximum value of g is:

• At the poles
• At the top of the Mount Everest
• At the equator
• Below the sea level

10. A fixed volume of gas at 27°C exerts a pressure of 750 mm. If the gas is heated to a pressure of 1500mm., temperature must be:

• 600°C
• 327°C
• 54°C
• 13.5°C

11. A body of mass 2 kg acted upon by a constant force, travels a distance of 3 metres in the first second and a further distance of meter in the next second. The force acting on the body is?

• 12 Newtons
• 8 Newtons
• 4 Newtons
• 1 Newton

12. Two forces each equal to P acting at a point have no resultant. The angle between the two forces must be equal to:

• 180°
• 90°
• 0°
• 120°

13. A jet engine works on the principle of:

• conservation of energy
• conservation of momentum
• conservation of mass
• conservation of temperature

14. A sharp knife cuts much better than a blunt one because?

• Area of sharp knife is much less than the area of the blunt one
• sharp knife is brighter
• sharp knife is colder
• sharp knife is costly

15. A man carries a heavy box on his head on a horizontal plane from one place to another. In this he does?

• maximum work
• no work
• negative work
• minimum work

16. The bob of a second’s pendulum is replaced by another bob of double mass.The new time period will be:

• 4 sec.
• 2 sec.
• 1 sec
• 3 sec.

17.A device for measuring temperatures at a distance is

• gas thermometer
• mercury thermometer
• radiation
• maximum-minimum thermometer

18. A piece of ice is floating in a concentrated solution of common salt (in water) in a pot. When ice melts completely, the level of solution will:

• go up
• remain the same
• go down
• first go up then go down

19. A radioactive source has a half-life of 30 days. During a period of 90 days the fraction of atoms that have decayed would be

• 100%
• 87.5%
• 64%
• 50%

20. A black body emits:

• radiations of all wavelengths
• no radiations
• radiations of only one wavelength
• radiations of selected wavelengths

21. A near sighted person cannot see distinctly beyond 50 cm. from his eye. The power in diopter of spectacle lenses which will enable him to see distant objects clearly is

• 50
• -50
• 2
• -2

22. Size of a nucleus is of the order of?

• 10-18m
• 10-14m
• 10-10m
• 10-6m

23. The freezing point on a thermometer is marked as 20° and the boiling point as 150°C. A temperature of 60°C on this thermometer will be read as:

• 40°
• 65°
• 98°
• 110°

24. In isothermal expansion of an ideal gas:

• heat content remains constant
• temperature remains constant
• both heat content and temperature remain constant
• pressure and temperature of the gas remain constant

25. A man standing between two cliffs hears the first echo of a sound after 2 sec. and the second echo 3 sec. after the initial sound. If the speed of sound be 330 m/sec. the distance between the two cliffs should be

• 1650 m.
• 990 m.
• 825 m
• 660 m.

26. In a resonance tube experiment the first resonance is obtained for 10 cm. of air column and the second for 32 cm. The end correction for this apparatus is equal to?

• 0.5 cm
• 1.0 cm
• 1.5 cm
• 2 cm

27. The ratio of the specific heat of air at constant pressure to its specific heat at constant volume is?

• zero
• greater than one
• less than one
• equal to one

28. A convex lens has a focal length of 10 cm. When it is immersed in water it will behave as?

• a convex tens of 10 cm. focal length
• a concave lens of 10 cm. focal length
• a convex lens of focal length greater than 10cm.
• a convex lens of focal length less than 10 cm.

29. Two particles having charges q1 and q2 when kept at a certain distance exert a force F on each other. If the distance between the two particles is reduced to half and the charge on each particle is doubled the force between the particles would be ?

• 2F
• 4F
• 8F
• 16F

30. A small magnet is placed perpendicular to a constant magnetic field. The forces acting on the magnet will result in?

• rotation
• translation
• no motion at all
• rotation as well as translation

31. A hollow metallic sphere is charged. Inside the sphere?

• the potential is zero but the electric field is finite
• the electric field is zero but the potential is finite
• both the electric field and the potential are finite
• both the electric field and the potential are zero

32. Two electric lamps each of 100 watts 220 V are connected in series to a supply of 220 volts. The power consumed would be:

• 100 Watts
• 200 Watts
• 25 Watts
• 50 Watts

33. A transformer is:

• a device for stepping up D.C.
• a generator of current
• device for converting direct current into alternating current
• a device for stepping up or down the voltage of A.C. supply

34. Transistor act as a?

• conductor
• semi-conductor
• insulator
• thermionic valve

35. The sky is blue because:

• there is more blue light in the sunlight
• of scattering of sunlight by air molecules in the atmosphere
• of scattering of sunlight by dust particles in the atmosphere
• other colours are absorbed by heavenly bodies

36. A cyclonic storm is indicated by a change in the atmospheric pressure.In atmospheric pressure there is a:

• sudden rise
• gradual rise
• sudden fall
• gradual fall

37. The electric field inside a hollow conducting sphere will ?

• increases towards the centre
• decreases towards the centre
• is finite and constant throughout
• is zero

38. Imperfect gases are those:

• which contain impurities
• which do not obey Charle’s and Boyle’s laws
• whose molecules are not spherical
• whose molecules cannot be regarded as point masses

39. Sonar is a device for:

• location and ranging of aircraft’s
• location and ranging submarines
• producing a musical note of high quality
• measuring frequency of musical notes

40. Cyclotron is a device to produce:

• atomic energy
• high energy electrons
• high energy photons
• high energy protons

41. Which one of the following is not a vector?

• Velocity
• Acceleration
• Force
• Energy

42. Two steel balls of mass 1 kg. and 2kg. and a lead ball of 10kg. are released together from the top of tower 30 metres high. Assuming the path to be in vacuum

• the lead ball reaches the ground earlier
• the 1 kg. steel bail reaches the ground earlier
• all the balls reach the ground simultaneously
• the 2 kg. steel ball reaches the ground earlier

43. After a watch has been wound, it?

• has great energy stored in it
• possesses mechanical potential energy stored in it
• has eletrical energy stored in it
• has no energy in it

44. Two plane mirrors are set at right angles and a flower is placed in any position in between the mirrors. The number of images of the flower which will be seen is?

• two
• four
• one
• three

45. In which of the following cases total internal reflection cannot be obtained?

• ray going from water to glass
• a ray going from glass to water
• a ray going from glass to air
• a ray going from water to air.

46. When white light passes through a glass prism, we get a spectrum on the other side of the prism. In the emergent beam the ray which is deviated least is

• the violet ray
• the red ray
• the green ray
• the yellow ray

47. Magnetic storms are due to

• the rotation of the earth
• the revolution of the earth
• the rainy season
• the appearance off Sun spots

48. For dynamo which one of the following statements is correct ?

• It converts the electrical energy into light energy
• It converts the kinetic energy into heat energy
• It converts the mechanical energy into electrical energy
• Jt converts the electrical energy into mechanical energy.

49. In a transformer the immediate cause of the induced A. C. in the secondary coil is?

• a varying electric field
• a varying magnetic field
• (e) a motion of the secondary coil
• efficiency of the operator

50.A dynamo actually acts as a?

• converter of energy
• source of electric charge
• source of magnetic charge
• source of energy

Read More

Prasar Bharti (All India Radio) Examination : Previous Year Solved Papers

Prasar Bharti (All India Radio) Examination 2011

Solved Question Paper with Answer

1. Which one of the following physical quantities, is not defined in the terms of force per unit area:

• pressure
• strain
• stress
• Young’s modulus

2. The distance moved by a moving body is equal to:

• area between the distance-time graph and distance axis
• area between the speed-time graph and time axis
• area between the distance-time graph and time axis
• area between the speed-time graph and distance axis.

3. A beaker containing water weighs 100 gm. It is placed on the pan of a balance and a piece of metal weighing 70 gm. and having a volume of 10cc. is placed inside the water in the beaker. The weight of the beaker and the metal would be :

• 170gm.
• 100gm.
• 160gm.
• 30gm.

4. For the same kinetic energy, the momentum shall be maximum for:

• electron
• proton
• deuteron
• alpha particle

5. The common balance works on the principle of equality of:

• forces
• moments of forces
• masses
• masses of pans

6. A particle moves in a circle of radius R with a constant speed under a centripetal force F. The work done in completing a full circle is:

• 2RF
• ?R2F
• 2?RF
• Zero

7. When two quantities are plotted on the graph paper against each other and the result so obtained is a st. line, then

• Both the quantities are equal
• The quantities are inversely proportional to each other
• Sum of both is zero
• The quantities are proportional to each other

8. What is the order of magnitude of 260°?

• 103
• 104
• 102
• 10

9. The maximum value of g is:

• At the poles
• At the top of the Mount Everest
• At the equator
• Below the sea level

10. A fixed volume of gas at 27°C exerts a pressure of 750 mm. If the gas is heated to a pressure of 1500mm., temperature must be:

• 600°C
• 327°C
• 54°C
• 13.5°C

11. A body of mass 2 kg acted upon by a constant force, travels a distance of 3 metres in the first second and a further distance of meter in the next second. The force acting on the body is?

• 12 Newtons
• 8 Newtons
• 4 Newtons
• 1 Newton

12. Two forces each equal to P acting at a point have no resultant. The angle between the two forces must be equal to:

• 180°
• 90°
• 0°
• 120°

13. A jet engine works on the principle of:

• conservation of energy
• conservation of momentum
• conservation of mass
• conservation of temperature

14. A sharp knife cuts much better than a blunt one because?

• Area of sharp knife is much less than the area of the blunt one
• sharp knife is brighter
• sharp knife is colder
• sharp knife is costly

15. A man carries a heavy box on his head on a horizontal plane from one place to another. In this he does?

• maximum work
• no work
• negative work
• minimum work

16. The bob of a second’s pendulum is replaced by another bob of double mass.The new time period will be:

• 4 sec.
• 2 sec.
• 1 sec
• 3 sec.

17.A device for measuring temperatures at a distance is

• gas thermometer
• mercury thermometer
• radiation
• maximum-minimum thermometer

18. A piece of ice is floating in a concentrated solution of common salt (in water) in a pot. When ice melts completely, the level of solution will:

• go up
• remain the same
• go down
• first go up then go down

19. A radioactive source has a half-life of 30 days. During a period of 90 days the fraction of atoms that have decayed would be

• 100%
• 87.5%
• 64%
• 50%

20. A black body emits:

• radiations of all wavelengths
• no radiations
• radiations of only one wavelength
• radiations of selected wavelengths

21. A near sighted person cannot see distinctly beyond 50 cm. from his eye. The power in diopter of spectacle lenses which will enable him to see distant objects clearly is

• 50
• -50
• 2
• -2

22. Size of a nucleus is of the order of?

• 10-18m
• 10-14m
• 10-10m
• 10-6m

23. The freezing point on a thermometer is marked as 20° and the boiling point as 150°C. A temperature of 60°C on this thermometer will be read as:

• 40°
• 65°
• 98°
• 110°

24. In isothermal expansion of an ideal gas:

• heat content remains constant
• temperature remains constant
• both heat content and temperature remain constant
• pressure and temperature of the gas remain constant

25. A man standing between two cliffs hears the first echo of a sound after 2 sec. and the second echo 3 sec. after the initial sound. If the speed of sound be 330 m/sec. the distance between the two cliffs should be

• 1650 m.
• 990 m.
• 825 m
• 660 m.

26. In a resonance tube experiment the first resonance is obtained for 10 cm. of air column and the second for 32 cm. The end correction for this apparatus is equal to?

• 0.5 cm
• 1.0 cm
• 1.5 cm
• 2 cm

27. The ratio of the specific heat of air at constant pressure to its specific heat at constant volume is?

• zero
• greater than one
• less than one
• equal to one

28. A convex lens has a focal length of 10 cm. When it is immersed in water it will behave as?

• a convex tens of 10 cm. focal length
• a concave lens of 10 cm. focal length
• a convex lens of focal length greater than 10cm.
• a convex lens of focal length less than 10 cm.

29. Two particles having charges q1 and q2 when kept at a certain distance exert a force F on each other. If the distance between the two particles is reduced to half and the charge on each particle is doubled the force between the particles would be ?

• 2F
• 4F
• 8F
• 16F

30. A small magnet is placed perpendicular to a constant magnetic field. The forces acting on the magnet will result in?

• rotation
• translation
• no motion at all
• rotation as well as translation

31. A hollow metallic sphere is charged. Inside the sphere?

• the potential is zero but the electric field is finite
• the electric field is zero but the potential is finite
• both the electric field and the potential are finite
• both the electric field and the potential are zero

32. Two electric lamps each of 100 watts 220 V are connected in series to a supply of 220 volts. The power consumed would be:

• 100 Watts
• 200 Watts
• 25 Watts
• 50 Watts

33. A transformer is:

• a device for stepping up D.C.
• a generator of current
• device for converting direct current into alternating current
• a device for stepping up or down the voltage of A.C. supply

34. Transistor act as a?

• conductor
• semi-conductor
• insulator
• thermionic valve

35. The sky is blue because:

• there is more blue light in the sunlight
• of scattering of sunlight by air molecules in the atmosphere
• of scattering of sunlight by dust particles in the atmosphere
• other colours are absorbed by heavenly bodies

36. A cyclonic storm is indicated by a change in the atmospheric pressure.In atmospheric pressure there is a:

• sudden rise
• gradual rise
• sudden fall
• gradual fall

37. The electric field inside a hollow conducting sphere will ?

• increases towards the centre
• decreases towards the centre
• is finite and constant throughout
• is zero

38. Imperfect gases are those:

• which contain impurities
• which do not obey Charle’s and Boyle’s laws
• whose molecules are not spherical
• whose molecules cannot be regarded as point masses

39. Sonar is a device for:

• location and ranging of aircraft’s
• location and ranging submarines
• producing a musical note of high quality
• measuring frequency of musical notes

40. Cyclotron is a device to produce:

• atomic energy
• high energy electrons
• high energy photons
• high energy protons

41. Which one of the following is not a vector?

• Velocity
• Acceleration
• Force
• Energy

42. Two steel balls of mass 1 kg. and 2kg. and a lead ball of 10kg. are released together from the top of tower 30 metres high. Assuming the path to be in vacuum

• the lead ball reaches the ground earlier
• the 1 kg. steel bail reaches the ground earlier
• all the balls reach the ground simultaneously
• the 2 kg. steel ball reaches the ground earlier

43. After a watch has been wound, it?

• has great energy stored in it
• possesses mechanical potential energy stored in it
• has eletrical energy stored in it
• has no energy in it

44. Two plane mirrors are set at right angles and a flower is placed in any position in between the mirrors. The number of images of the flower which will be seen is?

• two
• four
• one
• three

45. In which of the following cases total internal reflection cannot be obtained?

• ray going from water to glass
• a ray going from glass to water
• a ray going from glass to air
• a ray going from water to air.

46. When white light passes through a glass prism, we get a spectrum on the other side of the prism. In the emergent beam the ray which is deviated least is

• the violet ray
• the red ray
• the green ray
• the yellow ray

47. Magnetic storms are due to

• the rotation of the earth
• the revolution of the earth
• the rainy season
• the appearance off Sun spots

48. For dynamo which one of the following statements is correct ?

• It converts the electrical energy into light energy
• It converts the kinetic energy into heat energy
• It converts the mechanical energy into electrical energy
• Jt converts the electrical energy into mechanical energy.

49. In a transformer the immediate cause of the induced A. C. in the secondary coil is?

• a varying electric field
• a varying magnetic field
• (e) a motion of the secondary coil
• efficiency of the operator

50.A dynamo actually acts as a?

• converter of energy
• source of electric charge
• source of magnetic charge
• source of energy

Read More

Prasar Bharti Assistant Engineers Examination : Solved Question Paper

Prasar Bharti (All India Radio) Examination 2011

Assistant Engineer Exam
Solved Question Paper with Answer

Q. Lamps used for street lighting are connected in

• parallel
• series and parallel both
• series
• none of the above

Q. A. C. can be measured with the help of:

• moving coil galvanometer
• hot wire ammeter
• tangent galvanometer
• galvanometer

Q.A p-n junction is said to be forward biased, when

• the positive pole of the battery is joined to the p-semiconductor and negative pole to the n-semiconductor
• the positive pole of the battery is joined to the n-semiconductor and negative pole of the
• battery is joined to the p-semiconductor
• the positive pole of the battery is connected to n- semiconductor and p- semiconductor
• a mechanical force is applied in the forward direction

Q. At absolute zero, Si acts as ?

• non-metal
• metal
• insulator
• none of these

Q. When N-type semiconductor is heated ?

• number of electrons increases while that of holes decreases
• number of holes increases while that of electrons decreases
• number of electrons and holes remain same
• number of electron and holes increases equally.

Q. Radiowaves of constant amplitude can be generated with

• FET
• filter
• rectifier
• oscillator

Q. In a common base amplifier the phase difference between the input signal voltage & the output voltage is ?

• 0
• pi/4
• pi/2
• p

Q. When a triode is used as an amplifier the phase difference between the input signal voltage and the output is ?

• 0
• pi
• pi/2
• pi/4

Q. The depletion layer in the P-N junction region is caused by?

• drift of holes
• diffusion of charge carriers
• migration of impurity ions
• drift of electrons

Q. The following truth table corresponds to which Logic gate
A    B    Output
0     0      0
0     1      1
1     0      1
1     1      1

• NAND
• OR
• AND
• XOR

Q. To use a transistor as an amplifier

• The emitter base junction is forward biased and the base collector junction is reversed biased
• no bias voltage is required
• both junction are forward biased
• both junctions are reversed biased.

Q. Which one of the following is the weakest kind of the bonding in solids

• ionic
• metallic
• Vander Walls
• covalent

Q. For amplification by a triode, the signal to be amplified is given to

• the cathode
• the grid
• the glass-envelope
• the anode

Q. A piece of copper and other of germanium are cooled from the room temperature to 80K, then

• resistance of each will increase
• resistance of copper will decrease
• the resistance of copper will increase while that of germanium will decrease
• the resistance of copper will decrease while that of germanium will increase

Q. Diamond is very hard because ?

• it is covalent solid
• it has large cohesive energy
• high melting point
• insoluble in all solvents

Q. The part of the transistor which is heavily doped to produce large number of majority carriers is

• emitter
• base
• collector
• any of the above depending upon the nature of transistor

Q. An Oscillator is nothing but an amplifier with

• positive, feedback
• negative feedback
• large gain
• no feedback

Q. When a P-N junction diode is reverse biased the flow of current across the junction is mainly due to

• diffusion of charge
• drift charges
• depends on the nature o material
• both drift and diffusion of charges

Q. Which of the following gates corresponds to the truth table given below?
A     B     Output
1     1        0
0     1        1
1     0        1
0     0        1

• NAND
• OR
• AND
• XOR

Q. Which of the following, when added as an impurity, into the silicon, produces n-type semi conductor

• Phosphorous
• Aluminium
• Magnesium
• None Of These

Q. The current gain for a transistor working as common-base amplifier is 0.96. If the emitter current is 7.2 mA, then the base current is

• 0.29mA
• 0.35mA
• 0.39 mA
• 0.43 mA

Q. When a n-p-n transistor is used as an amplifier then ?

• the electrons flow from emitter to collector
• the holes flow from emitter to collector
• the electrons flow from collector to emitter
• the electrons flow from battery to emitter

Q. When arsenic is added as an impurity to silicon, the resulting material is?

• n-type semiconductor
• p-type semiconductor
• n-type conductor
• Insulator

Q. To obtain a p-type germanium semiconductor,it must be doped with ?

• arsenic
• antimony
• indium
• phosphorus

Q. A semi-conducting device is connected in a series circuit with a battery and a resistance. A current is found to pass through the circuit. If the polarity of the battery is reversed, the current drops to almost zero. The device may be

• A p-n junction
• An intrinsic semi-conductor
• A p-type semi-conductor
• An n-type semi-conductor

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Prasar Bharti Assistant Engineer Exam : Solved Questions With Answers

Prasar Bharti (All India Radio) Examination 2011

Assistant Engineer Exam
Solved Question Paper with Answer 

Q. The transfer ratio beta of a transistor is 50. The input resistance of the transistor when used in the common emitter configuration is 1 kohm. The peak value of the co current for an A.C. input voltage of 0.01 V peak is ?

• 100 microA
• 0.01 mA
• 0.25 mA
• 500 microA

Q. The cause of the potential barrier in a p-n diode is ?

• Depletion of positive charges near the junction
• Concentration of positive charges near the junction
• Depletion of negative charges near the junction
• Concentration of positive and negative charges near the junction

Q. In forward bias, the width of potential barrier in a p-n junction diode?

• increases
• decreases
• remains constant
• first increases then decreases

Q. A depletion lay consists of?

• electrons
• protons
• mobile ions
• immobile ions

Q. Which of the following when added acts as an impurity into silicon produced n-type semiconductor?

• P
• Al
• B
• Mg

Q. In a junction diode, the holes are due to

• protons
• extra electrons
• neutrons
• missing electrons

Q. The intrinsic semiconductor becomes an insulator at

• 0°C
• 0K
• 300K
• -100°C

Q. For a common emitter circuit if IC/IE = 0.98 then current gain for common emitter circuit will be

• 49
• 98
• (e)4.9
• 25.5

Q. In a p-n junction

• The potential of the p and n sides becomes higher alternately
• The p side is at higher electrical potential than the n side
• The n side is at higher electrical potential than the p side
• Both the p and n sides are at the same potential

Q. In the case of a common emitter transistor amplifier the ratio of the collector current to the emitter current Ic/Ie is 0.96. The current gain of the amplifier is ?

• 6
• 48
• 24
• 12

Q. if a full wave rectifier circuit is operating from 5oHz mains, the fundamental frequency in the tipple will be

• 100Hz
• 25Hz
• 50Hz
• 70.7 Hz

Q. A n-p-n transistor conducts when ?

• both collector and emitter are negative with respect to, the base
• both collector and emitter are positive with respect to the base
• collector is positive and emitter is negative with to the base
• collector is positive and emitter is at same potential as the base

Q. Barrier potential of a p-n junction diode does not depend on?

• doping density
• diode design
• temperature
• forward bias

Q. Reverse bias applied to a junction diode

• increases the minority carrier current
• lowers the potential barrier
• raises the potential barrier
• increases the majority carrier current

Q. In semiconductors at a room temperature

• the conduction band is completely empty
• the valence band is partially empty and the conduction band is partially filled
• the valence band is completely filled and the conduction band is partially filled
• the valence band is completely filled

Q. The output of OR gate is 1 when?

• if either input is zero
• if both inputs are zero
• if either or both inputs are 1
• only if both inputs are I

Q. In a p-n junction photo cell, the value of the photo-electromotive force produced by monochromatic light is proportional to ?

• the voltage applied at the p-n junction
• the barrier voltage at the p-n junction
• the intensity of the light falling on the cell
• the frequency of the light falling on the cell

Q. Choose the only false statement from the following.

• in conductors the valence and conduction bands may overlap.
• Substances with energy gap of the order of 10 eV are insulators.
• The resistivity of a semiconductor increases with increase in temperature.
• The conductivity of a semiconductor increases with increase in temperature.

Q. Carbon, Silicon and Germanium atoms have four valence electrons each. Their valence and conduction bands are separated by energy band gaps represented by (Eg)C, (Eg)Si and (Eg)Ge respectively. Which one of the following relationship is true in their case?

• (Eg)C> (Eg)Si
• (Eg)C< (Eg)Si 
• (Eg)C=(Eg)Si 
• (Eg)C< (Eg)Ge

Q. Application of a forward bias to a p—n junction 

• widens the depletion zone. 
• increases the potential difference across the depletion zone. 
• increases the number of donors on the n side. 
• increases the electric field in the depletion zone.

Q. Zener diode is used for? 

• Amplification 
• Rectification 
• Stabilisation 
• Producing oscillations in an oscillator

Q. A current carrying coil is subjected to a uniform magnetic field.The coil will orient so that its plane becomes ? 

• inclined at 45° to the magnetic field 
• inclined at any arbitrary angle to the magnetic field 
• parallel to the magnetic field 
• perpendicular to magnetic field

Q. Tesla is the unit of 

• magnetic flux 
• magnetic field 
• magnetic induction 
• magnetic moment

Q. Energy in a current carrying coil is stored in the form of ? 

• electric field 
• magnetic field 
• dielectric strength 
• heat

Read More

Prasar Bharti Assistant Engineer Exam : Solved Question Paper

Prasar Bharti (All India Radio) Examination 2011

Assistant Engineer Exam
Solved Question Paper with Answer

Q. Which one of the following physical quantities, is not defined in the terms of force per unit area :

• pressure
• strain
• stress
• Young’s modulus

Q. The distance moved by a moving body is equal to:

• area between the distance-time graph and distance axis
• area between the speed-time graph and time axis
• area between the distance-time graph and time axis
• area between the speed-time graph and distance axis.

Q. A beaker containing water weighs 100 gm. It is placed on the pan of a balance and a piece of metal weighing 70 gm. and having a volume of 10cc. is placed inside the water in the beaker.The weight of the beaker and the metal would be :

• 170gm.
• 100gm.
• 160gm.
• 30gm.

Q. For the same kinetic energy, the momentum shall be maximum for:

• electron
• proton
• deuteron
• alpha particle

Q. The common balance works on the principle of equality of:

• forces
• moments of forces
• masses
• masses of pans

Q. A particle moves in a circle of radius R with a constant speed under a centripetal force F.The work done in completing a full circle is:

• 2RF
• ?R2F
• 2?RF
• Zero

Q. When two quantities are plotted on the graph paper against each other and the result so obtained is a st. line, then

• Both the quantities are equal
• The quantities are inversely proportional to each other
• Sum of both is zero
• The quantities are proportional to each other

Q. What is the order of magnitude of 260°?

• 103
• 104
• 102
• 10

Q. The maximum value of g is:

• At the poles
• At the top of the Mount Everest
• At the equator
• Below the sea level

Q. A fixed volume of gas at 27°C exerts a pressure of 750 mm. If the gas is heated to a pressure of 1500mm., temperature must be:

• 600°C
• 327°C
• 54°C
• 13.5°C

Q. A body of mass 2 kg acted upon by a constant force, travels a distance of 3 metres in the first second and a further distance of meter in the next second. The force acting on the body is?

• 12 Newtons
• 8 Newtons
• 4 Newtons
• 1 Newton

Q. Two forces each equal to P acting at a point have no resultant. The angle between the two forces must be equal to:

• 180°
• 90°
• 0°
• 120°

Q. A jet engine works on the principle of:

• conservation of energy
• conservation of momentum
• conservation of mass
• conservation of temperature

Q. A sharp knife cuts much better than a blunt one because?

• Area of sharp knife is much less than the area of the blunt one
• sharp knife is brighter
• sharp knife is colder
• sharp knife is costly

Q. A man carries a heavy box on his head on a horizontal plane from one place to another. In this he does?

• maximum work
• no work
• negative work
• minimum work

Q. The bob of a second’s pendulum is replaced by another bob of double mass. The new time period will be:

• 4 sec.
• 2 sec.
• 1 sec
• 3 sec.

Q.A device for measuring temperatures at a distance is

• gas thermometer
• mercury thermometer
• radiation
• maximum-minimum thermometer

Q. A piece of ice is floating in a concentrated solution of common salt (in water) in a pot. When ice melts completely, the level of solution will:

• go up
• remain the same
• go down
• first go up then go down

Q. A radioactive source has a half-life of 30 days. During a period of 90 days the fraction of atoms that have decayed would be

• 100%
• 87.5%
• 64%
• 50%

Q. A black body emits:

• radiations of all wavelengths
• no radiations
• radiations of only one wavelength
• radiations of selected wavelengths

Q. A near sighted person cannot see distinctly beyond 50 cm. from his eye. The power in diopter of spectacle lenses which will enable him to see distant objects clearly is

• 50
• -50
• 2
• -2

Q. Size of a nucleus is of the order of?

• 10-18m
• 10-14m
• 10-10m
• 10-6m

Q. The freezing point on a thermometer is marked as 20° and the boiling point as 150°C. A temperature of 60°C on this thermometer will be read as:

• 40°
• 65°
• 98°
• 110°

Q. In isothermal expansion of an ideal gas:

• heat content remains constant
• temperature remains constant
• both heat content and temperature remain constant
• pressure and temperature of the gas remain constant

Q. A man standing between two cliffs hears the first echo of a sound after 2 sec.and the second echo 3 sec. after the initial sound. If the speed of sound be 330 m/sec. the distance between the two cliffs should be

• 1650 m.
• 990 m.
• 825 m
• 660 m.

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