# A 1000kg car, travelling east at 30.0m/s, collides with a 3000kg truck, travelling north. After the collision, the vehicles stick together and the combined wreckage moves at 55.0◦ north of east. (a) What is the speed of the truck before the collision?

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(b) What percentage of the initial kinetic energy of the system is lost during the collision?

(b) What percentage of the initial kinetic energy of the system is lost during the collision?

##### 1 Answer

(a)

(b)

#### Explanation:

(a) For all collisions where no external forces are involved, the linear momentum

is conserved.

Let the car move along the

After the collision both (combined wreckage) move at

From

From

--.-.-.-.-.-.-..-.-.-.-.-.-.-.-.-..-.-.-.-.-.-.-.-.-.-

(b) Kinetic energy before collision

Kinetic energy after collision

Now

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