Posted by Francesca on Friday, May 20, 2011 at 10:22am.
Two cars collide head on while each is travelling at 80 km/hr. Suppose all of their
kinetic energy is transformed into thermal energy. What is the temperature increase
of each car? [You may assume that the specific heat capacity of each car is that of
iron, 449 J kg1K1.]

Thermal Physics  drwls, Friday, May 20, 2011 at 11:03am
Divide the initial total kinetic energy (M V^2) by the heat capacity (2*M*C). M is the mass per car.
To compute total KE in Joules, note than you must first convert 80 km/h to 22.22 m/s. You must include a factor of 2 because there are two cars
Leave the mass as an unknown factor, M. It will cancel out
Then
delta T = V^2/(2 C)
where C is the specific heat
I get a T rise of 0.55 C (or K)