EASY
AS and A Level
IMPORTANT
Earn 100

The so-called 'zeroth law of thermodynamics' states that if the temperature of body A is equal to the temperature of body B and 

the temperature of body B is the same as body C, then the temperature of body C equals the temperature of body A. 
Explain, in terms of energy flow, why the concept of temperature would be meaningless if this law was not obeyed.

Important Questions on Thermal Physics

EASY
AS and A Level
IMPORTANT
 The first law of thermodynamics can be represented by the expression: U=q+W. State what is meant by all the symbols in this expression. 
EASY
AS and A Level
IMPORTANT

. Figure shows a fixed mass of gas that undergoes a change from A to B and then to C.

 During the change from A to B, 220 J of thermal energy (heat) is removed from the gas. Calculate the change in the internal energy of the gas.

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EASY
AS and A Level
IMPORTANT

Figure shows a fixed mass of gas that undergoes a change from A to B and then to C.

During the change from B to C, the internal energy of the gas decreases by 300 J. Using the first law of thermodynamics explain how this change can occur. 

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EASY
AS and A Level
IMPORTANT

When a thermocouple has one junction in melting ice and the other junction in boiling water it produces an e.m.f. of 63μV.

What e.m.f. would be produced if the second junction was also placed in melting ice?

EASY
AS and A Level
IMPORTANT

When a thermocouple has one junction in melting ice and the other junction in boiling water it produces an e.m.f. of 63μV.

When the second junction is placed in a cup of coffee, the e.m.f. produced is 49μV. Calculate the temperature of the coffee.

EASY
AS and A Level
IMPORTANT

When a thermocouple has one junction in melting ice and the other junction in boiling water it produces an e.m.f. of 63μV.

The second junction is now placed in a beaker of melting lead at 327°C.

Calculate the e.m.f. that would be produced.

EASY
AS and A Level
IMPORTANT

When a thermocouple has one junction in melting ice and the other junction in boiling water it produces an e.m.f. of 63μV.

The second junction is now placed in a beaker of melting lead at 327°C.

 State the assumption that you make.

EASY
AS and A Level
IMPORTANT

The resistance of a thermistor at 0°C is 2000 Ω. At 100 °C the resistance falls to 200 Ω. When the thermistor is placed in water of constant temperature, its resistance is 620 Ω.

Assuming that the resistance of the thermistor varies linearly with temperature, calculate the temperature of the water.