What is the KE before and after collision?

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a truck of a mass 2kg travels at 8m/s towards a stationary truck of mass 6kg. after colliding,the trucks link and move off together

A) what is the common velovity?

B) what is the KE before and after collision?

C) explain the apparent loss in energy

Help please :D
 
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lish said:
a truck of a mass 2kg travels at 8m/s towards a stationary truck of mass 6kg. after colliding,the trucks link and move off together

A) what is the common velovity?

For the before portion of the collision of the problem, only the momentum of the truck counts since the stationary truck is not moving. to calculate the common velocity, you know that the two masses are link together, so just sum the two masses. Now that you have your two masses sum together, and the initial velocity of the moving truck, you can easily find the common velocity.

B) what is the KE before and after collision?

Since you know the initial velocity, you can calculate the initial KE and once you calculate the final common velocity of the linked trucks, you can calculate the final KE of the two trucks.

C) explain the apparent loss in energy



Help please :D[/QUOTE]
 
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