What is the Temperature Increase of Cars Colliding at 80 km/hr?

AI Thread Summary
The discussion focuses on calculating the temperature increase of two cars colliding head-on at 80 km/hr, assuming all kinetic energy converts to thermal energy. The initial calculations used the kinetic energy formula and specific heat of iron but yielded an incorrect temperature increase. The error was identified as a unit conversion issue with the specific heat from J/(g*K) to J/(kg*K). After correcting this, the accurate temperature increase was determined to be 0.549 K. The thread highlights the importance of unit consistency in physics calculations.
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Homework Statement



Two cars collide head on while each is traveling at 80 km/hr. Suppose all their kinetic energy is transformed into the thermal energy of the wrecks. What is the temperature increase of each car? (Assume each car's specific heat is that of iron)

Homework Equations



K = .5mv^2
Q = cm(delta T)
iron specific heat = .449 J/(g*K)

The Attempt at a Solution



K = 2(.5m(22.2)^2) = 492.8m

(converted 80 km/hr to m/s)

Q = 492.8m = (.449)(2m)(delta T)
delta T = 548.8 KWhich is the wrong answer. I don't know what i am doing wrong. Can someone please help me. Thanks
 
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Got, it. Just needed to convert iron specific heat from J/(g*K) to J/(kg*K), so delta T is just .549
 

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