WBBSE For Class 9 Physical Science And Environment Chapter 6 Heat MCQS

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Chapter 6 Heat MCQs

Question 1. Calorimetry relates to the measurement of

  1. Heat
  2. Temperature
  3. Mechanical energy
  4.  None of these

Answer: (1) Heat

Question 2. The quantity of heat in a body depends on its

  1. Temperature
  2. Mass
  3. Material
  4. All of them

Answer: (4) All of them

Read And Learn More WBBSE Solutions For Class 9 Physical Science And Environment MCQS

Question 3. The quantity of heat is given by

  1. \(\frac{\mathrm{ms}}{\mathrm{t}}\)
  2.  mst
  3. \(\frac{\mathrm{mt}}{\mathrm{s}}\)
  4. \(\frac{\mathrm{st}}{\mathrm{m}}\)

Answer: (2) mst

Question 4. Work done W and heat produced H are related to each other (where J is the mechanical equivalent of heat

  1. WH = J
  2. H = JW
  3.  W = JH
  4.  WJH = 1

Answer: (3) W = JH

WBBSE For Class 9 Physical Science And Environment Chapter 6 Heat MCQS

WBBSE Class 9 heat chapter MCQs with answers

Question 5. The value of the mechanical equivalent of heat (in erg/calorie) is

  1. 4.2 x \(10^{-7}\)
  2. 4.2 x \(10^{7}\)
  3. \(\frac{1}{4.2}\)x \(10^{7}\)
  4.  4.2

Answer: (2) 4.2 x \(10^{7}\)

Question 6. The latent heat of the fusion of ice is

  1. 80 cal \(g^{-1}\)
  2. 3.36 x 105 cal \(g^{-1}\)
  3.  80 joule \(g^{-1}\)
  4. 3.36 cal \(g^{-1}\)

Answer: (1) 80 cal \(g^{-1}\)

Question 7. Saturated vapour obeys

  1.  Boyle’s law
  2. Charles’ law
  3. Pressure law
  4.  None of these laws

Answer: (1) Boyle’s law

Question 8. Dews are formed at a temperature

  1. Greater than dew point
  2. Less than dew point
  3. Equal to dew point
  4.  Independent of dew point

Answer: (4) Independent of dew point

Question 9. The volume of water is minimal at a temperature

  1.  − 4°C
  2. 4°C
  3.  o°C
  4. 1°C

Answer: (3) 0°C

Heat multiple choice questions for WBBSE Class 9

Question 10. The thermal capacity of a body of mass m and specific heat s is

  1. \(\frac{m}{s}\)
  2. \(\frac{s}{m}\)
  3. \(\frac{1}{\mathrm{~ms}}\)
  4. ms

Answer: (4) ms

Question 11. What is the unit of heat in the SI system?

  1. Calorie
  2. Joule
  3. Erg
  4. Newton

Answer: (2) Joule

Question 12. Who designed the absolute scale of temperature?

  1. Newton
  2. Lord Kelvin
  3. Celsius
  4. Boyle

Answer: (2) Lord Kelvin

Important heat chapter questions for Class 9 Physical Science

Question 13. Which substance has the highest specific heat?

  1. Water
  2. Iron
  3. Gold
  4. Ice

Answer: (1) Water

Question 14. The fundamental interval of the Celsius scale is divided into divisions.

  1. 100
  2. 180
  3. 120
  4. 102

Answer: (1) 100

Question 15. The fundamental interval of the Fahrenheit scale is divided into divisions.

  1. 180
  2. 100
  3. 32
  4. 212

Answer: (1) 180

WBBSE Class 9 Physical Science MCQs on heat and temperature

Question 16. If C and F represent two particular temperatures of Celsius and Fahrenheit scales respectively, they are related is

  1. \(\frac{C}{4}\)=\(\frac{F-32}{9}\)
  2. \(\frac{C}{5}\)=\(\frac{F-32}{9}\)
  3. \(\frac{C}{3}\)=\(\frac{F-32}{5}\)
  4. \(\frac{C}{9}\)=\(\frac{F-32}{5}\)

Answer: (2)\(\frac{C}{5}\)=\(\frac{F-32}{9}\)

Question 17. The instrument measures the temperature of a body

  1. Hydrometer
  2. Thermometer
  3.  Voltameter
  4. Ammeter

Answer: (2) Thermometer

Question 18. How many calories of heat would be produced by converting 42 joules of work completely into heat?

  1. 100 calories
  2. 10 calories
  3. 1000 calories
  4. 90 calories

Answer: (2) 10 calories

Question 19. The normal body temperature of a man is 

  1. 98.4°C
  2.  98.4°F
  3. 98.4 K
  4. 100°F

Answer: (2) 98.4°F

Solved MCQs on heat for WBBSE Class 9

Question 20. Which substance has the highest specific heat?

  1. Ethanol
  2. Water
  3. Acetone
  4. Ether

Answer: (2) Water

Question 21. If the specific heat of copper is 0.09, what will be the water equivalent of a block of copper of mass 50 g?

  1.  45g
  2. 4.5 g
  3. 450 g
  4. 44g

Answer: (2) 4.5 g

Question 22. What is the melting point of ice in Fahrenheit scale?

  1. 0°F
  2. 32°F
  3. 180°F
  4. 20°F

Answer: (2) 32°F

Question 23. What is the specific heat of water in the SI system?

  1. 42 joule
  2. 4200 joule/kg
  3. 4200 joule/kg K
  4. 42,000 joule/kg

Answer: (3) 4200 joule/kg K

Modes of heat transfer MCQs Class 9 WBBSE

Question 24. The dimension of heat is

  1. MLT
  2. \(\mathrm{ML}^{2} \mathrm{~T}^{-2}\)
  3. \(\mathrm{ML}^{-1} \mathrm{~T}^{-2}\)
  4. \(\mathrm{ML}^{-1} \mathrm{~T}^{-1}\)

Answer: (2) \(\mathrm{ML}^{2} \mathrm{~T}^{-2}\)

Question 25. Generally, the body temperature of a man is measured on a scale.

  1. Celsius
  2. Fahrenheit
  3. Kelvin
  4.  Reumer

Answer: (2) Fahrenheit

Question 26. Heat reaches the earth from the sun by the process of 

  1. Conduction
  2. Convection
  3. Radiation
  4.  None of these

Answer: (3) Radiation

Question 27. The value of the mechanical equivalent of heat in the CGS system is

  1.  4.18 x \(10^{7}\)erg/calorie
  2. 4.8 erg/calorie
  3. 5.18 x \(10^{7}\)erg/calorie
  4. 5.18 erg/calorie

Answer: (1) 4.18 x \(10^{7}\)erg/calorie

Question 28. How much work is to be done to produce 50 calories of heat?

  1. 210 joule
  2. 200 joule
  3. 20(1)joule
  4.  310 joule

Answer: (1) 210 joule

Question 29. The water equivalent of a body is equal to

  1.  Mass of the body x specific heat
  2. Mass of the body/specific heat
  3. Mass of the body + specific heat
  4.  Mass of the body − specific heat

Answer: (1) Mass of the body x specific heat

Question 30. Mercury remains in a liquid state for a range of temperature 

  1. − 39°C to 357°C
  2. − 57°C to 457°C
  3. − 10°C to 257°C
  4. −12°C to 122°C

Answer: (1) −39°C to 357°C

Best multiple choice questions on heat for WBBSE Class 9

Question 31. — 40°C is equal to

  1.  − 50°F
  2.  − 40°F
  3.  − 60°F
  4. − 80°F

Answer: (2) − 40°F

Question 32. 1°F is equal to

  1. \(\frac{5}{9}^{\circ} \mathrm{C}\)
  2. \(\frac{9}{5}^{\circ} \mathrm{C}\)
  3. \(\frac{8}{5}^{\circ} \mathrm{C}\)
  4. \(\frac{7}{5}^{\circ} \mathrm{C}\)

Answer: (1)\(\frac{5}{9}^{\circ} \mathrm{C}\)

Question 33. (1)calorie is equal to

  1. 4.18 Joule
  2. 5.18 Joule
  3.  3.18 Joule
  4.  4.18 Joule

Answer: (1) 4.18 Joule

Question 34. If the temperature in the Kelvin scale is T K and the temperature on the Celsius scale is t°C, then they are related as

  1.  T K = (273 + t °C)
  2. T K = (273 −t °C)
  3. T K = (273 t °C)
  4. TK = 0°C

Answer: (1) T K = (273 + t °C)

Question 35. Vapour cools when it

  1. Is kept under high pressure
  2. Suddenly expands
  3. Is confined in a closed vessel
  4. It is heated

Answer: (2) Suddenly expands

Question 36. The calorimeter is made of

  1. Glass
  2. Iron
  3. Aluminium
  4. Copper

Answer: (1) Glass

Question 37. When ice is kept under higher pressure its melting point

  1. Increases
  2. Decreases
  3. Remains unchanged
  4. Fluctuates

Answer: (2) Decreases

Question 38. When the temperature of a room equals the dew point, then the relative humidity of the room becomes

  1. 50%
  2. Zero
  3. 100%
  4. 20%

Answer: (3) 100%

Question 39. The saturated vapour pressure of water at 100°C is

  1.  78 cm
  2. 72 cm
  3. 76 cm
  4. 60 cm

Answer: (3) 76 cm

Question 40. A large chunk of ice melts at its bottom not at its upper surface because

  1. The bottom region exists at the surrounding temperature
  2.  Impurities are present at the bottom
  3. The weight of the ice exerts the surrounding pressure
  4. Impurities are present at the upper surface

Answer: (3) The Weight of the ice exerts the surrounding pressure

Question 41. Water boils when its saturated pressure

Becomes high

Equals the surrounding pressure

Becomes very low

Is zero

Answer: (2) Equals the surrounding pressure

Question 42. Cooking at high altitudes is more difficult because of

  1. High pressure
  2. High pressure and high boiling point
  3. Low pressure
  4. Low pressure and high boiling point

Answer: (3) Low pressure

Question 43. At the same temperature, 1g iron melts more ice than 1g lead, because

  1. The density of iron is greater than that of lead
  2.  The specific heat of iron is more than that of lead
  3. The latent heat of melting iron is more than that of lead
  4.  Iron is heavier than lead

Answer: (2) Specific heat of iron is more than that of lead

Question 44. A piece of ice at 0°C is dropped in water at 0°C. The piece of ice

  1. Will melt
  2. Part of the ice will melt
  3. Ice will not melt
  4. 1% of the ice will not

Answer: (1) Will melt

WBBSE Class 9 Physical Science latent heat and specific heat MCQs

Question 45. 50 g ice at 0°C is mixed in 50 g water at 20°C. The final temperature of the mixture will be

  1.  −10°C
  2.  −30°C
  3.  0°C
  4. 10°C

Answer: (4) 10°C

Question 46. Which of the following has two specific nests 2

  1. Solid
  2. Gas
  3. Liquid
  4.  Solid, liquid and gas

Answer: (3) Liquid

Question 47. Two blocks of lead of masses M and 2M are at the same temperature; heat contained by the heavier block is

  1. Half of that of M
  2. Equal to that of M
  3. Twice that of M
  4.  Four times that of M

Answer: (3) Twice that of M

Question 48. Which pair among the following denote the same physical quantity?

  1. Kelvin and Joule
  2.  Kelvin and Calorie
  3. Newton and Calorie
  4. Joule and Calorie

Answer: (4) Joule and Calorie

Question 49. The specific heat of a metallic body depends on

  1. Heat supplied to the body
  2. Increase in the temperature of the body
  3. Mass of the body
  4. Material of the body

Answer: (4) Material of the body

Question 50. The volume of some water is minimal at

  1.  100°C
  2.  0°C
  3.  4°C
  4. −4°C

Answer: (3) 4°C

Question 51. The volume of water in the temperature range from 0°C to 4°C

  1. Increases
  2. Decreases
  3. Remains the same
  4. May either increase or decrease

Answer: (2) Decreases

Question 52. The coefficient of expansion of water in the range 0°C to 4°C is

  1. Zero
  2.  Negative
  3. Positive
  4. Infinity

Answer: (2) Negative

Question 53. Due to the special behaviour of water, lakes and ponds freeze

  1. First at the bottom
  2. First in the middle layer
  3.  First at their surface
  4. Anywhere

Answer: (3) First at their surface

Question 54. The amount of heat required to raise the temperature of a body depends on

  1. The mass only
  2.  The temperature
  3. The specific heat only
  4. All three of them

Answer: (4) All three of them

Question 55. By definition (1)cal is equal to

  1. 1 J
  2. \(\frac{1}{4.186}\)
  3. 4.186 J
  4. None

Answer: (3) 4.186 J

Question 56. For m = mass of calorimeter and s = specific heat or the calorimeter material, the water equivalent of the calorimeter is

  1.  \(\frac{m}{s}\)
  2. \(\frac{m}{s}\)
  3. \(\mathrm{m}^2 s\)
  4. ms

Answer: (2)\(\frac{m}{s}\)

Question 57. Water boils at a temperature T (when pressure is 1.5 atm)

  1. T = 100°C
  2. T < 100°C
  3. T > 100°C
  4. None

Answer: (3) T > 100°C

Question 58. The heat of vaporization of water at 100°C is

  1. 4.186 J
  2.  539 J/g
  3. 539 cal/g
  4. 80 cal/g

Answer: (3) 539 cal/g

 

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