A thermometer and an electrical heater are inserted into holes in an aluminium block of mass 
, as shown in the figure below.
The power rating of the heater is 
. The heater is switched on and readings of the temperature of the block are taken at regular time intervals. When the block reaches a constant temperature, the heater is switched off and then further temperature readings are taken. After the heater has been switched off, the maximum rate of fall of temperature is 
per minute. Estimate the specific heat capacity of aluminium.
.
