A 1000-kg car moving east at 80 km/h collides head-on with a 1500-kg car moving west at 40 km/h, and the two cars stick together. (a) Which way does the wreckage move and with what initial speed? (b) How much KE is lost in the collision?
(a)
The final speed of the system.
Answer to Problem 58E
The final speed of the system is
Explanation of Solution
Given info: Mass of the first car is
Write the expression from conservation of momentum.
Here,
Substitute
Conclusion:
Therefore, the final speed of the system is
(b)
The amount of kinetic energy lost.
Answer to Problem 58E
The amount of kinetic energy lost is
Explanation of Solution
Given info: Mass of the first car is
Write the expression for kinetic energy lost.
Here,
Substitute
Conclusion:
The amount of kinetic energy lost is
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