Exercise for Physics – Basic Questions up to Class 10 Important for Exams – Must Know Logics Part 4

Get unlimited access to the best preparation resource for competitive exams : get questions, notes, tests, video lectures and more- for all subjects of your exam.

34. Match the following

Match the Following
List – I ParametersList – II Dependence
A. Intensity of light1. Properties of the medium
B. Colour of light2. Refractive index of the medium
C. Velocity of light3. Amplitude of light
D. Propagation of light4. Frequency of light

(a) 2 4 1 3

(b) 3 4 2 1

(c) 3 1 2 4

(d) 4 2 3 1

Ans: (b)

35. The most efficient engine is

(a) petrol

(b) diesel

(c) electric

(d) steam

Ans: (c)

36. Who invented the laser?

(a) Sir Frank whittle

(b) Fred Morrison

(c) Charles H Townes

(d) Seymour Cray

Ans: (c)

37. One astronomical unit is the average distance between

(a) Earth and the Sun

(b) Earth and the Moon

(c) Jupiter and the Sun

(d) Pluto and the Sun

Ans: (a)

38. When iron rusts, its weigh

(a) decreases

(b) increases

(c) shows no change

(d) decreases and then increases

Ans: (b)

39. Sound travels faster in

(a) dry air than in water

(b) wood than in iron

(c) iron than in air

(d) hydrogen than in water

Ans: (c)

40. We cannot see during a fog because of

(a) reflection of light

(b) internal reflection

(c) refraction

(d) scattering of light

Ans: (d)

41. Detergents dissolved in water help in cleaning clothes by

(a) increasing the temperature of water

(b) reacting chemically with dirt

(c) reducing the surface tension by water

(d) dissolving dirt

Ans: (c)

42. A remote control gadget (for TV etc.) has in it

(a) a small electromagnet, which emits electromagnetic waves

(b) a small oscillator that emits electric pulses

(c) a small transmitter that emits infrared signals

(d) None of the above

Ans: (c)

43. In storms, the roofs of some houses are carried away

This is in accordance with

(a) Bernoulli՚s principle

(b) Archimedes՚ principle

(c) Law of inertia

(d) Pascal՚s law

Ans: (a)

44. In Newton՚s third law, the action and reaction forces

1. act on different bodies

2. act on the same body

3. are not always equal

4. are always equal

Choose the correct answer from the codes given below

(a) 1 and 3 (b) 1 and 4

(c) 2 and 4 (d) 2 and 3

Ans: (b)

45. The phenomenon of mirage is due to

(a) increased absorption of light by air at higher temperature

(b) change in refractive index of air with change in temperature

(c) total internal reflection

(d) decreased absorption of light by air at higher temperature

Ans: (c)

46. Which law is involved in the act of cleaning a carpet by beating it with a stick?

(a) First law of motion

(b) Second law of motion

(c) Law of conservation of energy

(d) Law of conservation of mass

Ans: (a)