Units and Dimensions MCQs Quiz Multiple Choice Questions & Answers

1. ..............is needed for the experimental verification of various theories.

1. Unit
2. Symbol
3. Instrument
4. Measurement

2. A ..............is the interval from one noon to the next noon.

1. mean solar day
2. solar day
3. lunar day
4. day

3. A set of fundamental and derived units is known as

1. supplementary units
2. system of units
3. complementary units
4. metric units

4. A unitless quantity

1. always has a non-zero dimension.
2. may have a non-zero dimension.
3. never has a zero dimension.
4. has no dimensions.

5. Accidental error can be minimised by

1. taking only one reading.
2. taking small magnitude of the quantity.
3. selecting instrument with greater least count.
4. selecting instrument with small least count.

6. Checking the correctness of physical equations using the method of dimensions is based on

1. equality of inertial frame of reference.
2. the type of system of units.
3. the method of measurement.
4. principle of homogeneity of dimensions.

7. Constant error can be caused due to

1. faulty construction of instrument.
2. wrong setting of instrument.
3. lack of concentration of observer.
4. wrong procedure of handling the instrument

8. Dimensional equation CANNOT be used

1. to check the correctness of a physical quantity.
2. to derive the relation between different physical quantities.
3. to find out constant of proportionality which may be pure number.
4. to change from one system of units toanother system.

9. Error due to non-removal of parallax between pointer and its image in case of magnetic compass needle causes

1. instrumental error
2. persistant error
3. personal error
4. random error

10. If the pointer of the voltmeter is not exactly at the zero of the scale then the error is called

1. instrumental error
2. systematic error
3. personal error
4. random error

11. In cesium atomic clock ..............is used.

1. cesium-122 atom
2. cesium-132 atom
3. cesium-133 atom
4. cesium-134 atom

12. In which of following system, scientific data can be exchanged between different parts of the world?

1. M.K.S.
2. C.G.S.
3. F.P.S.
4. S.I

13. Instrumental error can be minimised by

1. taking large number of readings.
2. using different accurate instrument for the same reading.
3. adjusting zero of the instrument.
4. maintaining the temperature of the surrounding.

14. Light year is a unit for the measurement of

1. distance
2. time
3. temperature
4. luminous intensity

15. Maxwells equations relate to

1. law of gravitation
2. basic laws of electromagnetism
3. laws of electrostatics
4. nuclear model of an atom

16. Nano size of gold has ..............colour.

1. yellow
2. red
3. pink
4. orange

17. Out of the following units, which is NOT a fundamental unit?

1. newton
2. second
3. pound
4. kg

18. S.I system of unit contains ..............supplementary unit.

1. 7
2. 2
3. many
4. 4

19. Significant figures depends upon the ..............of the measuring instrument.

1. length
2. readings
3. number
4. accuracy

20. State the number of significant figures in6.032 J

1. 4
2. 3
3. 2
4. 1

21. Temperature can be expressed as a derived quantity in terms of

1. length and mass
2. mass and time
3. length, mass and time
4. none of these

22. The atomic, molecular and nuclear phenomena are the parts of ..............domain.

1. macroscopic
2. microscopic
3. megascopic
4. electroscopic

23. The difference between the true value and measured value is called

1. mistake
2. error
3. significant figures
4. fault

24. The magnitude of the difference between mean value and each individual value is called

1. absolute error
2. error in reading
3. most probable error
4. true error

25. The mass of the body depends only on

1. temperature.
2. pressure.
3. quantity of matter contained in the body.
4. location of the body from the observer

26. The number of significant figures in 0.0009 is

1. 4
2. 3
3. 2
4. 1

27. The number of significant figures in 0.0500 is

1. 4
2. 3
3. 2
4. 1

28. The number of significant figures in 0.400 is

1. 1
2. 2
3. 3
4. 4

29. The physical quantity having the same unit in all the systems of unit is

1. length
2. time
3. mass
4. foot

30. The reference standard used for the measurement of a physical quantity is called

1. standard quantity
2. dimension
3. constant
4. unit

31. The SI unit of luminous intensity is

1. watt
2. lux
3. lumen
4. candela

32. The value of the magnitude rounded off to the nearest integral power of 10 is called

1. significant figure
2. uncertain number
3. significant number
4. order of magnitude

33. To measure the distance of a planet from the earth ..............method is used.

1. echo
2. direct
3. parallax
4. paradox

34. Units are classified into ..............groups.

1. 2
2. 4
3. 5
4. 6

35. Universal time is based on

1. rotation of the earth on its axis.
2. Earths orbital motion around the Sun.
3. vibrations of cesium atom.
4. oscillations of quartz crystal.

36. Which of the following is a supplementary unit?

1. steradian
2. candela
3. kelvin
4. pascal

37. Which of the following is NOT a characteristic of a good unit?

1. It is invariable.
2. It is reproducible.
3. It is perishable.
4. It is easily available

38. Which of the following is NOT a derived unit?

1. joule
2. erg
3. dyne
4. mole

39. Which of the following is NOT a dimensionless quantity?

1. angle
2. strain
3. specific gravity
4. density

40. Which of the following is the CORRECT way of writing units?

1. 25 ms length
2. 30 Kg
3. 5 Newton
4. 10 N

41. Which of the following quantity is expressedas force per unit area?

1. work
2. pressure
3. volume
4. density

42. Zero error of an instrument introduces

1. systematic error
2. random error
3. instrumental error
4. none of these