The temperature inside a refrigerator is 4°C and the room tempera...
Coefficient of performance(cop) of a refrigerator,
β= Q2/Q1-Q2=T2/T1-T2=277/300-277=277/23≈12
OR, Q2/W=12. Therefore, W=1J.Q2=12J
Also, Q1=Q2+W
=(12+1) J
=13J
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The temperature inside a refrigerator is 4°C and the room tempera...
The temperature inside a refrigerator is 4°C and the room tempera...
To determine the amount of heat delivered to the room for each joule of electricity consumed by the refrigerator, we need to calculate the heat transfer between the refrigerator and the room.
The heat transfer between two objects can be determined using the formula:
Q = m * c * ΔT
Where:
Q = heat transfer (in joules)
m = mass of the substance (in kilograms)
c = specific heat capacity of the substance (in joules per kilogram per degree Celsius)
ΔT = change in temperature (in degrees Celsius)
In this case, we can assume that the mass of the substance is constant and equal to the mass of the air inside the refrigerator. The specific heat capacity of air is approximately 1005 J/kg°C.
Using the given temperatures, we can calculate the change in temperature:
ΔT = room temperature - refrigerator temperature
= 27°C - 4°C
= 23°C
Hence, the heat transfer can be calculated as:
Q = m * c * ΔT
Since we are interested in the heat delivered to the room per joule of electricity consumed, we can calculate the ratio of Q to the electricity consumed.
Let's assume the electricity consumed by the refrigerator is 1 joule.
Therefore, the heat delivered to the room per joule of electricity consumed can be calculated as:
Heat delivered per joule of electricity consumed = Q / 1 joule
Calculating the value of Q using the formula:
Q = m * c * ΔT
= m * 1005 J/kg°C * 23°C
Assuming the mass of air inside the refrigerator is 1 kg, we can calculate:
Q = 1 kg * 1005 J/kg°C * 23°C
= 23,115 J
Hence, the heat delivered to the room per joule of electricity consumed is:
Heat delivered per joule of electricity consumed = 23,115 J / 1 J
= 23,115 J
Therefore, the correct answer is option D) 23 J.
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