Temperature and its Measurement Part 3: MCQs (Q51–Q75)

Part 3 — Questions 51–75 (Applications, conversions, and practical aspects)

51. Which thermometer is used by doctors to check patient’s fever?

A. Laboratory thermometer
B. Clinical thermometer ← Correct Answer
C. Pyrometer
D. Alcohol thermometer
Explanation:
A) Not for humans.
B) Correct — clinical thermometer (35–42°C).
C) For very high temps.
D) For cold climates, not fever.

52. Why can’t a clinical thermometer be used for measuring boiling water?

A. No scale above 50°C
B. Glass breaks at 100°C
C. Its range is only 35–42°C ← Correct Answer
D. Mercury evaporates instantly
Explanation:
A/D) Wrong.
B) Glass may not always break.
C) Correct — beyond 42°C, thermometer breaks.

53. Which device records maximum and minimum daily temperature?

A. Six’s thermometer ← Correct Answer
B. Clinical thermometer
C. Digital thermometer
D. Barometer
Explanation:
A) Correct — Six’s thermometer (weather).
B/C/D) Not for this purpose.

54. Heat transfer in liquids and gases mainly occurs by

A. Conduction
B. Convection ← Correct Answer
C. Radiation
D. Reflection
Explanation:
A) Mostly in solids.
B) Correct — convection currents in fluids.
C/D) Not primary mode.

55. Which of the following prevents parallax error in reading a thermometer?

A. Tilting glass
B. Keeping eye at mercury level ← Correct Answer
C. Reading from top angle
D. Using mirror at base
Explanation:
A/C/D) Wrong.
B) Correct — avoid parallax error by level reading.

56. Which of the following scales has no negative values?

A. Celsius
B. Fahrenheit
C. Kelvin ← Correct Answer
D. Reaumur
Explanation:
A/B/D) Allow negatives.
C) Correct — Kelvin starts at 0 (absolute zero).

57. Which instrument is used for measuring very high furnace temperature?

A. Laboratory thermometer
B. Clinical thermometer
C. Pyrometer ← Correct Answer
D. Alcohol thermometer
Explanation:
A/B/D) Not suitable.
C) Correct — pyrometer works at >1000°C.

58. When mercury contracts in a thermometer, it shows

A. Decrease in temperature ← Correct Answer
B. Increase in temperature
C. Increase in pressure
D. No change
Explanation:
A) Correct — contraction = lower temp.
B–D) Wrong.

59. Which unit is smaller?

A. 1°C
B. 1°F ← Correct Answer
C. 1 K
D. 10°C
Explanation:
A/C/D) Larger increments.
B) Correct — 1°F is smaller than 1°C.

60. Which statement is correct about digital thermometers?

A. Use mercury
B. Use electronic sensors to display readings ← Correct Answer
C. Cannot measure body temperature
D. Always inaccurate
Explanation:
A) No mercury.
B) Correct — sensors replace mercury.
C/D) Wrong.

61. Which of these is NOT a precaution for clinical thermometer?

A. Do not use in hot liquids
B. Do not bite bulb
C. Shake before use
D. Hold by bulb ← Correct Answer
Explanation:
A/B/C) True precautions.
D) Correct — hold by stem, not bulb.

62. 273 K is equal to

A. 0°F
B. 100°C
C. 0°C ← Correct Answer
D. –273°C
Explanation:
A/D) Wrong.
B) 373 K = 100°C.
C) Correct — 273 K = 0°C.

63. Which thermometer uses alcohol instead of mercury?

A. Clinical
B. Alcohol thermometer (for cold climates) ← Correct Answer
C. Pyrometer
D. Digital
Explanation:
A/C/D) Wrong.
B) Correct — alcohol thermometers measure very low temps.

64. When temperature of a liquid increases, what happens to its volume?

A. Decreases
B. Constant
C. Increases due to expansion ← Correct Answer
D. Becomes zero
Explanation:
A/B/D) Wrong.
C) Correct — liquids expand when heated.

65. 37°C in Fahrenheit is

A. 70°F
B. 98.6°F ← Correct Answer
C. 32°F
D. 120°F
Explanation:
A/C/D) Wrong.
B) Correct — normal body temp = 98.6°F.

66. Which is an advantage of alcohol over mercury in thermometers?

A. Poor visibility
B. Works in very low temperature (below –39°C) ← Correct Answer
C. Cannot expand uniformly
D. More poisonous
Explanation:
A/C/D) Wrong.
B) Correct — alcohol remains liquid at very low temps.

67. Which material is used for thermometer capillary?

A. Plastic
B. Thin glass tube ← Correct Answer
C. Copper wire
D. Steel rod
Explanation:
A/C/D) Not used.
B) Correct — glass capillary holds mercury/alcohol.

68. Why should thermometer bulb be fully dipped in the liquid?

A. To look nice
B. So bulb liquid reaches same temp as liquid ← Correct Answer
C. To fill it with water
D. To prevent mercury freezing
Explanation:
A/C/D) Wrong.
B) Correct — ensures accurate measurement.

69. Which thermometer is used by meteorologists?

A. Maximum–minimum thermometer ← Correct Answer
B. Clinical thermometer
C. Digital only
D. Mercury barometer
Explanation:
A) Correct — used for weather forecasting.
B/C/D) Wrong instruments.

70. What is the “absolute zero” temperature?

A. 0°C
B. –100°C
C. –273°C or 0 K ← Correct Answer
D. 100 K
Explanation:
A/B/D) Wrong.
C) Correct — no molecular motion at absolute zero.

71. The heat energy required to change state without changing temperature is called

A. Specific heat
B. Latent heat ← Correct Answer
C. Sensible heat
D. Potential energy
Explanation:
A/C/D) Wrong.
B) Correct — latent heat causes phase change at constant temp.

72. Which part of thermometer is graduated?

A. Bulb
B. Stem with scale ← Correct Answer
C. Mercury thread
D. Glass cover only
Explanation:
A/C/D) Not marked.
B) Correct — scale on stem.

73. 0°C corresponds to how many Kelvin?

A. 0 K
B. 32 K
C. 100 K
D. 273 K ← Correct Answer
Explanation:
A/B/C) Wrong.
D) Correct — 0°C = 273 K.

74. Which statement is FALSE about mercury thermometers?

A. Shiny and visible
B. Expands uniformly
C. Safe and non-toxic ← Correct Answer
D. Freezes at –39°C
Explanation:
A/B/D) True.
C) Correct — mercury is poisonous, unsafe if broken.

75. Which liquid expands more for the same rise in temperature?

A. Mercury
B. Alcohol ← Correct Answer
C. Water
D. Oil
Explanation:
A/C/D) Expand less.
B) Correct — alcohol expands more than mercury, easier to observe.

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