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Thermodynamics

Description: Thermodynamics
Number of Questions: 15
Created by:
Tags: Thermodynamics Science and Technology
Attempted 0/15 Correct 0 Score 0

Consider the following statements:

  1. The thermal power plant of India with the highest installed capacity is situated in West Bengal.
  2. Uranus is the hottest planet in the solar system.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2


Correct Option: A
Explanation:

Statement 1 is correct. MTPS (Mejia Thermal Power Station) is the largest thermal power plant in terms of generating capacity. It is located in West Bengal. Statement 2 is incorrect. Venus is the hottest planet in the solar system.

Consider the following statements: (i) Compressed air coming out from a punctured ball becomes hotter. (ii) A sudden fall in the reading of a barometer indicates the sign of coming storm.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2


Correct Option: B
Explanation:

Statement 1 is incorrect. Compressed air coming out from a punctured ball becomes cooler as every expanding gas produces cooling effect. Statement 2 is correct. Barometer is a scientific instrument used to measure the atmospheric pressure. From a sudden fall in mercury of a barometer, a thunderstorm may be expected.

Which of the following types of utensil is the most suitable for cooking the food?

  1. High specific heat and low conductivity

  2. High specific heat and high conductivity

  3. Low specific heat and low conductivity

  4. Low specific heat and high conductivity


Correct Option: D
Explanation:

'Specific heat' means the heat required to warm up and 'conductivity' means ability to conduct heat/electricity. The utensils used for cooking food should have low specific heat and high conductivity.

Consider the following statements:

  1. Saw dust is a bad conductor of heat.
  2. Water at 0o C feels colder than ice at 0o C.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2


Correct Option: A
Explanation:

Statement 1 is correct. Ice is generally covered with star dust as it is a poor conductor of heat. Statement 2 is incorrect. Ice at 0o C feels colder than water at 0o C due to latent heat of fusion (quantity of heat required to change liquid substance to solid).

Consider the following substances:

  1. Melting point of a substance increases on adding impurity.
  2. If the temperature of the surrounding is increased, the clock will lose the time.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2


Correct Option: B
Explanation:

Statement 1 is incorrect. Melting point of a substance decreases on adding impurity. Melting points are associated with packaging of molecules of substance. With the addition of impurities between the molecules, it decreases the melting point. Statement 2 is correct. When the temperature increases, the metallic pendulum expands. So, it takes more time to complete one oscillation. So, the clock loses time (goes slow).

Consider the following statements:

  1. In refrigerator, the heat engine works in backward direction.
  2. The temperature of the upper part of the flame is more than the temperature on the sides.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2


Correct Option: C
Explanation:

Statement 1 is correct. Refrigerator is an apparatus, which takes heat from a cold body, and work on it. Statement 2 is also correct. The temperature of the upper part of the flame is more than the temperature on the sides because the currents of air carry the heat upwards.

Consider the following statements:

  1. Highly polished surfaces are bad absorbers of heat.
  2. Heat helps in increasing the shelf life of food items.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2


Correct Option: C
Explanation:

Statement 1 is correct. Highly polished surfaces are bad absorbers of heat. The back grill of a refrigerator is painted black for the purpose. Statement 2 is also correct. Heat can kill the harmful bacteria and germs. This property of heat helps in keeping the food items, preserved for a longer time.

Consider the following statements:

  1. Conduction of heat can take place in vacuum.
  2. In a room, ventilators are provided at the ceiling for hot air to escape by conduction.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2


Correct Option: D
Explanation:

Statement 1 is incorrect. Conduction of heat does not take place in vacuum. Conduction only takes place in solids. Statement 2 is also incorrect. In a room, ventilators are provided at the ceiling for hot air to escape by convection. Convection takes place in liquids and gases.       

Consider the following statements:

  1. The temperature at which ice, water and steam co-exists is called triple point.
  2. Due to large specific heat capacity, hot water bottles are used to provide heat energy.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2


Correct Option: C
Explanation:

Statement 1 is correct. Triple point is the temperature at which ice, water and steam co-exists. Statement 2 is also correct. Due to large specific heat capacity, hot water bottles are used to provide heat energy.

Consider the following statements:

  1. During severe winter, the superficial parts of the lakes are frozen leaving water below because of low conductivity of ice.
  2. Land breeze occurs usually during day time.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2


Correct Option: A
Explanation:

Statement 1 is correct. During severe winter, the superficial parts of the lakes are frozen leaving water below because of low conductivity of ice. Statement 2 is incorrect. Land breeze occurs usually during night. A land breeze is a type of wind that blows from the land to the ocean. When there is a temperature difference between the land surface and the ocean, winds will move offshore. It is usually occur at night.

Consider the following statements:

  1. Hot water extinguishes fire more effectively than cold water.
  2. When vapour condenses into liquid, it absorbs heat.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2


Correct Option: A
Explanation:

Statement 1 is correct. The fire extinguishing involves absorption of heat. The absorption of heat in converting hot water to steam is higher than the heat absorbed in heating cold water to the boiling temperature. Hot water readily converts to steam absorbing enormous amount of heat and therefore hot water is better for fire extinguishing purpose than cold water. Statement 2 is incorrect. When vapour condenses into liquid, it liberates heat.

In a cup, tea cools from 90 degree Celsius to 80 degree Celsius in exactly 1 minute. It will cool from 70 degree Celsius to 60 degree Celsius in

  1. less than one minute

  2. exactly one minute

  3. nearly one minute

  4. more than one minute


Correct Option: D
Explanation:

The time required to cool down a liquid is directly proportional to the heat to be extracted. The evaporation produces cooling effect. More is the evaporation rate, more easily the liquid becomes cool.

Consider the following statements:

  1. Calorimeter an apparatus is used for measuring heat energy.
  2. Human body is an example of closed system.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2


Correct Option: A
Explanation:

Statement 1 is correct. A calorimeter is an object used for calorimetry, or the process of measuring the heat of chemical reactions or physical changes as well as heat capacity. Statement 2 is incorrect. Human body is an example of open system. Open system is a system, which can exchange matter as well as energy with the surroundings is called an open system.

Consider the following statements:

  1. A thermometer indicates 98.6 oC that it may be in a normal person's mouth.
  2. The formation of ice from water is accompanied by absorption of energy as heat.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2


Correct Option: B
Explanation:

Statement 1 is incorrect. A thermometer indicates 98.6 0C that it may be in a cup of hot tea. The normal body temperature of a man is nearly 370 C or 970 F. Statement 2 is correct. The formation of ice from water is accompanied by absorption of energy as heat to break or decrease the number of intermolecular forces.

Consider the following statements:

  1. Ice cream boxes are covered with glass wool because it allows the leakage of heat.
  2. Steam engine transforms heat into mechanical energy.

Which of the given statements is/are correct?

  1. Only 1

  2. Only 2

  3. Both 1 and 2

  4. Neither 1 nor 2


Correct Option: B
Explanation:

Statement 1 is incorrect. Ice cream boxes are covered with glass wool because it is a bad conductor of heat. It does allow the transfer tof heat from surroundings to inside the box. Statement 2 is correct. Steam engine transforms heat into mechanical energy. The burning of coal produces heat, which produces the force to spin the steam turbine for the production of electricity.

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