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Unfortunately, Mr. M. Subramanian, who maintained this website lost his battle to cancer and passed away in July, 2019. The database has over 50,000 questions. If you are interested in purchasing the website/database, please reach out using the form here.

Q1. If the sum of all the forces acting on a moving object is zero, the object will

Slow down and stop

Change the direction of its motion

Accelerate uniformly

Continue moving with constant velocity.

Q2. If the mass of one man is 60 kg on the earth, what is his mass on moon?

60 kg

360 kg

10 kg

240 kg

Q3. If the scattered light has a wavelength different from that of incident light it is called

Scattering

Coherent scattering

Rayleigh’s scattering

Incoherent scattering.

Q4. If the mass of an object is increased by 4 times and velocity is halved, the K.E will be

Half of previous K.E

Same as previous KE

Double of previous KE

Cannot be predicted

Q5. If the K.E of a body becomes four times of its initial value, then the new momentum will be

Unchanged

Twice its initial value

Four times its initial value

Three times its initial value.

Q6. If the glasses or contact lens prescribed for a person has a positive power, then he is suffering from

Astigmatism

Presbyopia

Myopia

Hypermetropia

Q7. If the frequency of light wave is 5 × 1014 Hz and its wave length in a medium is 400 Å. What is the refractive index of the material medium?

1.4

1.33

1.5

Q8. If the density of blood is 1040 kgm3 then the minimum pressure required to force blood from the heart to top of the head for a vertical distance of 0.5 cm is

6 × 103

5 × 103

60 × 103

70 ×103

Q9. If the current flowing through an electric circuit is doubled then heat produced by the current in the electric circuit is the initial value.

One time

Twice

Three times

Four times.

Q10. If the current flowing through a filament lamp of power 60W is lA, find its resistance.

60 W

6 W

0.02 W

.5 W

Q11. If the area of cross-section of a conductor is doubled, what is its resistance ?

Doubled

Remains the same

Be halved

Becomes one-fourth

Q12. If no external force acts on the object, what will be the acceleration?

Zero

Minimum

Maximum

Equal to 1

Q13. If mass of an object is m, velocity v, acceleration a and applied force is f and momentum is p .......

P = ma

P = mv

P = m/v

P = v/m

Q14. If four resistors each of value 10W are connected in series, then the total resistance of the circuit is

40 W

0.125 W

5 W

Q15. If density of air is 1.3 kg/m3 and coefficient of viscosity is 187 × 10–7 NSm–2 then the vertical velocity for air flowing through a tube of 10–2 m radius is

0.72 ms–1

1.44 ms–1

2.44 ms–1

0.44 ms–1

Q16. If an object is placed in front of a convex lens at a distance less than the focal length, then the image formed is ......... and .........

Diminished, erect

Diminished, inverted

Magnified erect

Magnified, inverted. .

Q17. If an object is placed at a distance of 10 cm from the optic centre of a convex lens, of focal length 12 cm, the nature of the image is

real and erect

real and inverted

Virtual and inverted

Virtual and erect

Q18. If an incident ray makes an angle of 16 degree with the normal to the plane mirror, then the angle, between .the reflected ray and the. plane mirror is

74 degree

86 degree

106 degree

16 degree.

Q19. If an electric kettle is marked 220 V. 1 kw, the maximum current at which it can be safely operated is

0.166666666666667

4.5 A

3.5A

Q20. If a mirror has a focal length of +10cm then it is a

Concave

Convex

Plane

Semi Silvered

Q21. If a mirror has a focal length of + 10 cm then it is a

Concave mirror

Convex mirror

Plane mirror

Semi silvered mirror

Q22. If a Microwave oven has the rating of 1100 W, 220 V marked on it, what should be minimum rating of the fuse put by the electrician in the part of the circuit?

0.208333333333333

0.416666666666667

2.5 A

15 A

Q23. If a magnet is cut into two pieces of equal length

Both pieces will lose their magnetism

One piece is north and the other piece is south pole

Both piece will behave as complete magnets

One piece will lose magnetism.

Q24. If a greased needle is gently placed on the surface of water, it

Sinks

Floats

Vibrates

Oscillates

Q25. If a convex lens of focal length 15 cm forms an image at 35 cm, the distance of the object is

–22cm

–19cm

–26.25 cm

–17.5 cm

Q26. If a camphor is placed on the surface of water the surface tension

Increases at the point

Decreases at the point

Decreases or increases

Neither increases nor decreases

Q27. If a body reflects all the colours that fallon it in what colour does it appear?

Blue

Red

Yellow

White.

Q28. Hydrogen atom does not have

Proton

Neutron

Electron

Proton and electron.

Q29. How will you find the magnitude of the +ve charge?

Q = Z/e

Q = Z e

Q = Z e2

Q = e/z

Q30. How will you convert galvanometer into voltmeter?

High resistance in series

High resistance in parallel

Low resistance in series

Low resistance in parallel.

Q31. How will you convert galvanometer into ammeter?

By connecting high resistance in parallel

Low resistance in series

High resistance in series

Low resistance in parallel.

Q32. How will you connect fuse wire with an electric device?

Parallel

Series

None of the above

Q33. How to increase induced current in a coil?

Using stronger coil

.Using a stronger magnet

Using a smaller coil

None of the above

Q34. How to locate pole star while observing the constellations?

With help of great bear

Orion

with the help of Cassiope

None of the above.

Q35. How to demagnetize a permanent magnet?

Stopping the current

Passing DC of high voltage

Placing it inside a solenoid carrying AC

Passing DC of low voltage.

Q36. How to demagnetize a permanent magnet?

Passing DC current of high voltage through it

Stopping the current

Placing it inside a solenoid carrying alternating current

Passing DC current of low voltage.

Q37. How to change the focal length of an eye1ens?

By the action of pupil

By retina

Ciliary muscles

By the action of iris.

Q38. How much temperature is required for nuclear fission reaction to take place?

10–7 k

105 k

107 k

1017 k

Q39. How much voltage should be applied to a 50W resistance, to produce 1000J of heat in 10 seconds?

5000 V

250 V

70.71 V

700.7 V

Q40. How much solar energy is received by each square meter of upper atmosphere per second?

1.36 KJ/s

2.36 KJ/s

0.36 J/s

1. 76 J/s

Q41. How much percentage of U238 present in natural uranium?

0.7 %

99.3 %

98.9 %

Q42. How much potential is required to produce X- rays?

1000 v

1,00,000 v

10,000 v

100 v.

Q43. How much heat is generated when current I is passing through a resistor for time t?

12 Rt

IR2 t

I2R

Q44. How much of the energy in burning coal reaches the consumer as electricity?

1/3

1/2

3/4

9/10

Q45. How much energy will 20 kg of a fuel yield on complete combustion, if the calorific value is 50 kJ/gm?

105 KJ

106 KJ

103 KJ

104 KJ

Q46. How much heat energy is produced in 10 s in an electric iron having resistance 440W when a potential of 220 V is applied?

1200 J

1100 J

600 J

1000 J

Q47. How much energy is required for passing 1000 electrons through a 10 V source?

104 ev

106 ev

1.6 × 10–15 J

1000 ev

Q48. How much energy is released. during nuclear fusion?

17.6 Mev

16.7 Mev

17.6 Kev

16.7 Kev

Q49. How much energy is released when 17 I 33 is bomborded with a neutron?

200 Mev

935 Mev

17.6 Mev

0.935 Mev

Q50. How much energy is released per fission of 9aU235?

200 M ev

200 ev

20 M ev

2 Mev.

Answers Evaluate

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