A car of mass $1400$ kg travelling at $25$ m$/$s on a flat road performs an emergency stop and  comes to rest. The car is decelerated via friction on $4$ steel brake discs of mass $1\mathrm{.}5$ kg each, at temperature of $20$ ⁰ Celsius before braking.

Assuming that the car tyres do not skid, the mechanical energy of the car is dissipated as 

heat energy shared equally between the discs, and the specific heat capacity of steel is c $=510$ Joule$/($ kg K$)$ calculate the temperature of the brake discs when the car stops.

 

 

 

 

 

 

Answer rating: 100% (QA)

To calculate the temperature of the brake discs when the car stops we can use the principle of conse... View the full answer