Refrigeration & Air Conditioning Mcqs

Q:

The effective temperature increases with a decrease in relative humidity at the same DBT.

A) True B) False
 
Answer & Explanation Answer: B) False

Explanation: At the same value of dry bulb temperature, the effective temperature decreases with a decrease in relative humidity to achieve desired comfort conditions.

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12
Q:

Which of the following does not mainly a factor of dependency for the degree of warmth or cold?

A) Relative humidity B) WBT
C) Air velocity D) DBT
 
Answer & Explanation Answer: D) DBT

Explanation: The degree of warmth or cold felt by the human body depends mainly on dry bulb temperature, air velocity and relative humidity.

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15
Q:

When the heat stored in the body is ________ the human body feels comfortable.

A) zero B) infinite
C) positive D) negative
 
Answer & Explanation Answer: A) zero

Explanation: The human body feels comfortable when the heat stored in the body is zero. This is the desired comfort condition.

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14
Q:

The heat production from a normal healthy man when asleep is about _________

A) 50 W B) 40 W
C) 70 W D) 60 W
 
Answer & Explanation Answer: D) 60 W

Explanation: A normal healthy man when asleep produces heat nearly equal to 60 W. This might vary depending on various parameters.

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20
Q:

Which of the following is true about the optimum effective temperature for human comfort?

A) Same in winter and summer B) Not dependent on season
C) Lower in winter than in summer D) Higher in winter than in summer
 
Answer & Explanation Answer: C) Lower in winter than in summer

Explanation: Optimum effective temperature is dependent on climatic and seasonal changes. So, for human comfort, the optimum effective temperature is lower in winter than in summer.

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12
Q:

What is the effective temperature needed in a hall with a high density of occupants?

A) Higher B) Lower
C) Much higher D) Has no effect of density of occupants
 
Answer & Explanation Answer: A) Higher

Explanation: A hall filled with a huge number of people require lower effective temperature than a hall having lesser density. Due to the radiant heat transfer from person to person.

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15
Q:

What is the effective temperature needed if a person is sitting in a cinema hall?

A) Higher B) Lower
C) Much lower D) Has no effect of kind of activity
 
Answer & Explanation Answer: A) Higher

Explanation: Kind of activity a person does, affect the effective temperature. If the person works on heavy loads in a factory or gym, then that person will need a low effective temperature. On the contrary, if a person is doing less activity like sitting in a hall to watch movies, then that person will need a higher effective temperature than people doing heavy work.

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11
Q:

What is the effective temperature needed if a person is doing a heavy activity like working with heavy loads?

A) Higher B) Lower
C) Much higher D) Has no effect of kind of activity
 
Answer & Explanation Answer: B) Lower

Explanation: Kind of activity a person does, affect the effective temperature. If the person works on heavy loads in a factory or gym, then that person will need a low effective temperature.

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