1. A particle is moving uniformly with an angular velocity ? on the circumference of a circle of
radius r. The linear velocity will be given by
(a) r?
(b)2?r?
(c) r/?
(d) ?/r
Ans:a
2. Line spectrum is obtained from the?
(a) Sun
(b) Filament of the bulb
(c) Mercury lamp
(d) Burning coal
Ans:c
3. A moving charge produces:
(a) neither electric field nor magnetic field
(b) electro-static field only
(c) magnetic field only
(d) both magnetic and electro-static fields
Ans:c
4. ?, ? and ?rays emitted from a radioactive source are passed through a 0.5 cm. thick aluminum
sheet. The out going radiations will consist of:
(a) ?, ? and ?ray
(b) ? and ?ray
(c) ?ray
(d) ?rays
Ans:b
5. Light year is a unit of
(a) time
(b) distance
(c) velocity
(d) acceleration
Ans:b
6. It is easier to draw up wooden block along an inclined plane than bang it up vertically
principally because:
(a) the friction is reduced
(b) only a part of the weight has to be overcome
(c) the mass becomes smaller
(d) g becomes smaller
Ans:b
7. If a piece of ice floating on the surface of water in a beaker melts completely, the level of
water
(a) rises
(b) remains the same
(c) falls
(d) initially rises and then falls
Ans:b
8. A Kelvin thermometer and a Fahrenheit thermometer used to record temperature of melting
metal, read the same. What will a celcius thermometer read at that temperature?
(a) 301.25°
(b) 273°
(c) 457°
(d) 760°
Ans:a
9. A hydrogen-filled balloon expands as it rises and may even burst after rising very high in the
atmosphere. This happens because:
(a) the temperature increases with height
(b) the temperature decreases with height
(c) the atmospheric pressure increases with height
(d) the atmospheric pressure decreases with height
Ans:d
10. if two substances of equal volumes but of different densities are dropped from the same
height simultaneously, then
(a) the body of lower density will reach the earth earlier
(b) both the bodies will reach the earth simultaneously
(c) The body of higher density will reach earlier
(d) It depends upon the place
Ans:b
11. When the bob of a pendulum is at the mean position (minimum displacement) of its motion,
its total energy is:
(a) all potential
(b) zero
(c) all kinetic
(d) partly kinetic partly potential
Ans:c
12. A red and a green pencil are taken in a room illuminated with green light. In the room:
(a) both pencils will appear dark
(b) pencils will appear as red and green respectively
(c) red pencil.will appear dark and green pencil as green
(d) red pencil will appear red and green pencil dark
Ans:c
13. The consumption of electrical energy in the household is measured in terms of:
(a) Kilowatt hour
(b) Kilowatts
(c) Joules
(d) Kilo Joules
Ans:a
14. A magnet is placed in earth’s magnetic field with north pole of the magnet pointing north. At
the neutral point:
(a) the earth’s magnetic field is zero
(b) the magnet’s magnetic field is zero
(c) the fields of the magnet and the earth are equal and in the same direction
(d) the fields of the magnet and the earth are equal and opposite
Ans:d
15. Sudden fall of a barometer reading indicates:
(a) storm
(b) dry weather
(c) fine weather
(d) cold weather
Ans:a
16. If a ball and a rectangular block of different metal when completely immersed in a liquid,
have the same loss of weight, then
(a) ball and rectangular block have same density
(b) ball and rectangular block have Weight in air
(c) ball and rectangular block have same volume
(d) ball and rectangular block have immersed to the same depth
Ans:c
17. If the period of oscillation of a simple pendulum is 4 seconds and we want to convert it into a
second pendulum, then we have to:
(a) make the length of the pendulum one fourth of the previous length
(b) double the length of the pendulum
(c) make the length of the pendulum half of the previous length
(d) double the mass of the bob
Ans:a
18. The escape velocity of a body from the earth depends upon:
(a) mass of the body
(b) radius of the earth as well as the value of g
(c) the radius of the earth only
(d) volume of the body
Ans:b
19. A cyclist taking a turn bends inside because:
(a) he feels pleasure in doing so
(b) he increases speed in doing so
(c) he obtains necessary Centripetal force
(d) he avoids accidents
Ans:c
20. If the surface of water in a lake is just going to freeze, then the temperature of water at the
bottom is
(a) 0°C
(b) 4°C
(c) 3°C
(d) none of these
Ans:b
21. The tangent law is applicable only when:
(a) there are at least two magnetic fields
(b) there two uniform magnetic fields mutually perpendicular to each other
(c) one strong magnetic field and the other weak magnetic field
(d) in the present magnetic fields one should be horizontal component of the earth’s magnetic
field
Ans:b
22. A moving coil galvanometer is converted into an ammeter by putting:
(a) a high resistance in parallel
(b) a low resistance in series
(c) a low resistance in parallel
(d) a high resistance in series
Ans:c
23. Lenz’s law is derived from the law of conservation of:
(a)momentum
(b) energy
(c)charge
(d) magnetism
Ans:b
24. On which one of the factors does the sensivity of a galvanometer depend?
(a) number of the turns of the coil
(b) the temperature of the room
(c) the current flowing in it
(d) the potential difference between the two ends.
Ans:a
25. The wavelength of X-rays is of the order of:
(a) 0.1 cm
(b) 10 2cm
(c)10 -4cm
(d)10 -8cm
Ans:d
26. Lamps used for street lighting are connected in
(a) parallel
(b) series and parallel both
(c) series
(d) none of the above
Ans:a
27. A. C. can be measured with the help of:
(a) moving coil galvanometer
(b) hot wire ammeter
(c) tangent galvanometer
(d) galvanometer
Ans:b
28.A p-n junction is said to be forward biased, when
(a) the positive pole of the battery is joined to the p-semiconductor and negative pole to the nsemiconductor
(b) the positive pole of the battery is joined to the n-semiconductor and negative pole of the
battery is joined to the p-semiconductor
(c) the positive pole of the battery is connected to n- semiconductor and p- semiconductor
(d) a mechanical force is applied in the forward direction
Ans :a
29. At absolute zero, Si acts as ?
(a) non-metal
(b) metal
(c) insulator
(d) none of these
Ans :a
30. When N-type semiconductor is heated ?
(a) number of electrons increases while that of holes decreases
(b) number of holes increases while that of electrons decreases
(c) number of electrons and holes remain same
(d) number of electron and holes increases equally.
Ans :d
31. Radiowaves of constant amplitude can be generated with
(a) FET
(b) filter
(c) rectifier
(d) oscillator
Ans :d
32. In a common base amplifier the phase difference between the input signal voltage and the
output
voltage is ?
(a) 0
(b) pi/4
(c)pi/2
(d) p
Ans :d
33. When a triode is used as an amplifier the phase difference between the input signal voltage
and the output is ?
(a) 0
(b)pi
(c) pi/2
(d)pi/4
Ans :b
34. The depletion layer in the P-N junction region is
caused by?
(a) drift of holes
(b) diffusion of charge carriers
(c) migration of impurity ions
(d) drift of electrons
Ans: b
35. The following truth table corresponds to which Logic gate
A B Output
0 0 0
0 1 1
1 0 1
1 1 1
(a)NAND
(b) OR
(c)AND
(d) XOR
Ans :b
36. To use a transistor as an amplifier
(a) The emitter base junction is forward biased and the base collector junction is reversed biased
(b) no bias voltage is required
(c) both junction are forward biased
(d) both junctions are reversed biased.
Ans :a
37. Which one of the following is the weakest kind of the bonding in solids
(a) ionic
(b) metallic
(c) Vander Walls
(d) covalent
Ans :c
38.For amplification by a triode, the signal to be amplified is given to
(a) the cathode
(b) the grid
(c) the glass-envelope
(d) the anode
Ans :b
39. A piece of copper and other of germanium are cooled from the room temperature to 80K,
then
(a) resistance of each will increase
(b) resistance of copper will decrease
(c) the resistance of copper will increase while that of germanium will decrease
(d) the resistance of copper will decrease while that of germanium will increase
Ans:d
40. Diamond is very hard because ?
(a) it is covalent solid
(b) it has large cohesive energy
(c) high melting point
(d) insoluble in all solvents
Ans:b
41. The part of the transistor which is heavily doped to produce large number of majority carriers
is
(a) emitter
(b) base
(c) collector
(d) any of the above depending upon the nature of transistor
Ans:a
42. An Oscillator is nothing but an amplifier with
(a) positive, feedback
(b) negative feedback
(c)large gain
(d) no feedback
Ans:a
43. When a P-N junction diode is reverse biased the flow of current across the junction is mainly
due
to
(a) diffusion of charge
(b) drift charges
(c) depends on the nature o material
(d) both drift and diffusion of charges
Ans:b
44. 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
(a) NAND
(b) OR
(c) AND
(d) XOR
Ans:a
45. Which of the following, when added as an impurity, into the silicon, produces n-type semi
conductor
(a)Phosphorous
(b) Aluminium
(c)Magnesium
(d) both ‘b’ and ‘c’
Ans:a
46. 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
(a)0.29mA
(b)0.35mA
(c)0.39 mA
(d) 0.43 mA
Ans:a
47. When a n-p-n transistor is used as an amplifier then ?
(a) the electrons flow from emitter to collector
(b) the holes flow from emitter to collector
(c) the electrons flow from collector to emitter
(d) the electrons flow from battery to emitter
Ans:a
48. When arsenic is added as an impurity to silicon, the resulting material is?
(a) n-type semiconductor
(b) p-type semiconductor
(c) n-type conductor
(d) Insulator
Ans:a
49. To obtain a p-type germanium semiconductor,it must be doped with ?
(a)arsenic
(b)antimony
(c)indium
(d)phosphorus
Ans:a
50. 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) A p-n junction
(b) An intrinsic semi-conductor
(c) A p-type semi-conductor
(d) An n-type semi-conductor
Ans:a
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