Finding the specific heat capacity of a block
A student is carrying out an investigation to find the specific heat capacity of an unknown block. He measures the energy supplied to it as he heats it.
The results obtained are shown below:
mass of block: 0.831 kg
original temperature of block: 13.1 degrees C
final temperature of block: 41.3 degrees C
Energy supplied: 23800 J
a) Define specific heat capacity
b) Use the measurements to calculate the specific heat capacity of the block.
Because he knows it is good practice to repeat an experimental procedure, the student carries out a repeat experiment, supplying the same amount of energy. This time he obtains the following readings:
original temperature of block: 41.0 degrees C
final temperature of block: 62.1 degrees C
c) Use these values to calculate a second specific heat capacity for the block.
The student did not make any mistakes when taking his readings.
d) Suggest why the second reading is greater than the first?
e) Suggest two methods of improvement that would allow the student to obtain similar values each time?
Always study the experimental set up carefully: they will usually ask you to improve it!
Try to include as much detail as possible in your definition!
Remember specific heat capacity can be found using the formula
Energy = mass x specific heat capacity x change in temperature
but you'll have to rearrange it!
Think about what a greater specific heat capacity means: did more or less energy have to be transfered to the block this time?
How could you prevent this loss in energy?