What is the Kinetic and Internal Energy of a Car-Truck Collision?

AI Thread Summary
The discussion focuses on calculating the kinetic and internal energy of a car-truck collision involving a 1200 kg car and a 7600 kg truck. The car is initially traveling at 88 km/h and the truck at 65 km/h, with both vehicles sticking together post-collision at 68 km/h. The kinetic energy of the center of mass of the combined system is to be determined, along with the internal energy before and after the collision. Key equations include the conservation of momentum and the kinetic energy formula. The conversion of speeds from km/h to m/s is necessary for accurate calculations.
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Homework Statement



A 1200 kg car moving at 88 km/h collides with a 7600 kg truck moving in the same direction at 65 km/h. The two stick together, continuing in their original direction at 68 km/h. Determine the kinetic energy of the center of mass of the (car + truck) system. Determine the internal energy of the (car + truck) system before the collision. Determine the internal energy of the (car + truck) system after the collision.

Homework Equations



m1v1 + m2v2 = (m1 + m2)vf

Kinetic energy of a system is K = Kcm + Kint

K = 1/2mv2

The Attempt at a Solution



88 km/h converted to 24.4444 m/s
65 km/h converted to 18.0556 m/s
 
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You'd need to find the velocity of the (car+truck) system after collision to get the kinetic energy.
 

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