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Q1. Who predicted that the change in both electric and magnetic field cause electro magnetic disturbances?

Hertz

Maxwell

Newton

Planck·

Q2. What is the difference between CFL and an LED lamp? (1) To produce light, a CFL uses mercury vapour and phosphor while an LED lamp uses semi conductor material. (2) The average life span of a CFL is much longer than that of an LED lamp. (3) A CFL is less energy efficient as compared to an LED lamp

1 only

2 and 3 only

1 and 3 only

all of them

Q3. Who produced electromagnetic wave of wavelength about 6 m?

J.C. Bose

Marconi

Hertz

J. Ritter.

Q4. What is the difference between Bluetooth and WiFi devices?

Blue Tooth uses 2.4 GHz radio frequency band, whereas WiFi can use 2.4 GHz or 5 GHz frequency band

Bluetooth is used for Wireless Local Area Networks (WLAN) only, where WiFi is used for Wireless Wide Area Networks (WWAN) only

When information is transmitted between two devices using Bluetooth technology, the devices have to be in the line of sight of each other, but when WiFi technology is used the devices need not be in the line of sight of each other.

The statements (a) and (b) given above are correct in this context.

Q5. Who produced electromagnetic waves experimentally?

Maxwell

Hertz

Planck

Faraday.

Q6. Who proposed Heliocentric theory?

Ptolemy

Aryabhatta

Copernicus

Brahma Gupta.

Q7. Who showed that a current carrying conductor placed in magnetic field experiences a mechanical force?

Hans Christian Oersted

Ampere

Michael Faraday

Lenz

Q8. Who stated that in the absence of air resistance all bodies fall at the same acceleration?

Sir Issac Newton

Albert Einstain

Gallilio

John Kepler

Q9. Who succeeded in converting magnetism to electricity ?

Faraday

Ampere

Haris Christian Oersted

Fleming

Q10. Who suggested that electrons are embedded in a + ve charged sphere?

Thomson

Bohr

Dalton

Rutherford

Q11. Who was the first chairman of atomic energy commission?

Dr. Homi. J. Bhabha

Dr. Abdul Kalam

Dr. Krishna Menon

Dr. Vikram Sara Bhai

Q12. Why are coal, oil and natural gas non-renewable resources?

They contain carbon compounds

They cannot be replaced, except over million of years

Once used. They cannot be used again.

None of these

Q13. Why are moderators used?

Slow down neutrons

Slow down fast moving electrons

Speed up the neutrons

Fasten up protons.

Q14. Why are transformers used in the national grid?

Less energy is lost from wires at high voltage

Less energy is lost from wires at low voltage

They are needed to convert DC into AC

None of the abvoe

Q15. Why are uranium and plutonium used as nuclear fuels?

They are metals

They release a lot of heat when they burn

They are radioactive.

None of the above

Q16. Why does a well cut diamond appear bright?

It emits light

It is radioactive

Total internal reflection

Dispersion.

Q17. Why does the sky appear dark instead of blue to an astronaut?

Scattering

Interference

Refraction

Absence of scattering.

Q18. Why fuse wire is used in an electrical circuit?

To increase the current

To control voltage fluctuations

To break the circuit when excessive current flows

To decrease the flow of current in the circuit.

Q19. Why gamma rays are not deflected?

They are positive charged

They are negative charged

Chargeless

Either positive or negative

Q20. Why IR rays are scattered well?

Longer wavelength

Shorter wavelength

Small frequency

High penetrating power.

Q21. Why is the green house building constructed with glass?

To protect soil

To protect atmosphere

To protect plants

To protect water.

Q22. Why is tungsten used as filament in bulbs?

Low melting point

High melting point

Tensile strength

Non-metal

Q23. Why steel wires are used to suspend heavy load?

Due to strong adhesive force

Due to strong cohesive force

Due to viscous force

Due to strong repulsive force.

Q24. Why x- rays are not deflected .by electric and magnetic fields?

Because they are Charged

Uncharged

+vely charged

-vely charged.

Q25. With an increase of temperature, in a metallic conductor, the conductivity and resistivity

Decreases, increases

Increases, decreases

Decreases, decreases

Increases, increases

Q26. Work done (W) is moving a charge (Q) between two points in an electric field. What is the potential difference (V)

V = IR

Q = NE

V = W+ Q

W = VQ

Q27. Work is done only when .............. .

Applied force generates motion

Applied force is strong

Applied force is normal to the displacement

Force is applied.

Q28. X- rays are used for

Physiotherapy

Treatment of arthritis

Communication purposes

Diagnostic purposes.

Q29. X-rays are ..............

Deflected by electric fields

Deflected by magnetic fields

Deflected by both electric and magnetic fields

Not deflected by both the fields

Q30. X-rays are electromagnetic waves of ..............

Long wavelength

Short wavelength

Very long wavelength

Very short wavelength

Q31. X-rays are used to find ............

pH of blood

Targets during war time

Bullets, pins. coins etc. in human body

Submerged ships in navigation.

Q32. X-rays can penetrate through ...............

Flesh but not through cardboard

Flesh but not through bones

Skin but not through Flesh

Lead but not through aluminium.

Q33. X-rays travel in ............ line.

Curved

Deviated

Un continuous

Straight.

Q34. X-rays travel with the velocity of

Light

Sound

9.8ms–1

Alpha

Q35. Which one of the following types of waves are used in a night vision apparatus?

Radio waves

Microwaves

Infra-red waves

None of these

Q36. Which one of the following has the highest energy?

Blue Light

Green Light

Red Light

Yellow Light

Q37. A person is sitting in a car which is at rest. The reaction from the road at each of the four wheels of the car is R. When the car runs on a straight level rroad, how will the reaction at either of the front wheels vary?

it will be greater than R

It will be less than R

It will be equal to R

it shall depend on the material of the road

Q38. Consider the following statements: (1) The albedo of an object determines its visual brightness when viewed with reflected light. (2) The albedo of Mercury is much greater than the albedo of the Earth. Which of the statements given above is/are correct?

1 only

2 only

Both 1 and 2

Neither 1 nor 2

Q39. Assertion (A): In the visible spectrum of light, red light is more energetic than green light. Reason {R}: The wavelength of red light is more than that of green light.

Both A and R are individually true and R is the correct explanation of A

Both A and R are individually true but R is not the correct explanation of A

A is true but R is false

A is false but R is true.

Q40. Which one of the following non-metals is not a poor conductor of electricity?

Sulphur

Selenium

Bromine

Phosphorus

Q41. Which one of the following types of glass can cut off ultraviolet rays.

Soda glass

Pyrex glass

Jena glass

Crookes glass

Q42. Consider the following statements: (1) A flute of smaller length produces waves of lower frequency. (2) Sound travels in rocks in the form of longitudinal elastic waves only. Which of the statements give above is/are correct?

1 only

2 only

both 1 and 2

neither 1 nor 2

Q43. Four wires of same material and of dimensions as under are stretched by a load of same magnitude separately. Which one of them will be elongated maximum?

Wire of 1 m length and 2mm diameter

wire of 2 m length and 2mm diameter

Wire of 3 m lenth and 1.5 mm diameter

wire of 1 m length and 1mm diameter

Q44. Assertion (A): A jet aircraft moving at Mach Number equal to 1 travels faster at an altitude of 15 km than while moving at Mach Number equal to 1 near the sea level. Reason ({R}: The velocity of sound depends on the temperature of the surrounding medium.

Both A and R are individually true and R is the correct explanation of A

Both A and R are individually true but R is not the correct explanation of A

A is true but R is false

A is false but R is true.

Q45. Three identical vessels A, B and C are filled with water, mercury and kerosene respectively up to an equal height. The three vessels are provided with identical taps at the bottom of the vessels. If the three taps are opened simultaneously, then which vessel is emptied first?

Vessel B

All the vessels will be emptied simultaneously

Vessel A

Vessel C

Q46. In which one among the following is the speed of sound maximum?

Air at 0 degreeC

Air at 100 degreeC

Water

Wood

Q47. What does the term ' Dollby B " or ' Dolby C " printed on tape recorders and other sound systems refer to?

Frequently modulated system

Amplitude modulated system

Noise Reduction Circuit

Both DC and AC power can be used.

Q48. A car is running on a road at a uniform speed of 60 km/hr. The net resultant force on the car is .....

Driving force in the direction of car's motion

Resistance force opposite to the direction of car's motion

An inclined force

Equal to zero

Q49. Assertion (A): In our houses, the current in AC electricity line changes direction 60 times per second. Reason {r}: The frequency of alternating voltage supplied is 60 hertz.

Both A and R are individually true and R is the correct explanation of A

Both A and R are individually true but R is not the correct explanation of A

A is true but R is false

A is false but R is true

Q50. Regarding the atom of a chemical element, the magnetic quantum number refers to .....

orientation

shape

size

spin

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