Question

Two cars collide at an intersection. Car A, with a mass of 1900 kg , is going from west to east, while car B , of mass 1500 kg , is going from north to south at 12 m/s . As a result of this collision, the two cars become enmeshed and move as one afterwards. In your role as an expert witness, you inspect the scene and determine that, after the collision, the enmeshed cars moved at an angle of 65 ∘ south of east from the point of impact. Part A Part complete How fast were the enmeshed cars moving just after the collision? Express your answer using two significant figures. v = 5.8 m/s Previous Answers Correct Part B How fast was car A going just before the collision? Express your answer using two significant figures. How fast were the enmeshed cars moving just after the collision and how fast was car A going just before the collision?

Answer 1

Where, u is velocity of car A before collision

v is velocity of enmeshed cars after collision

Before Collision :

Total momentum of the system is

  

After collision :

Total momentum of the system is

Applying conservation of momentum, we get

or,

or we can write,

................................(1)

and

or,

Putting the value of ' v ' in equation (1), we get

or,

or,

Hence, the enmeshed car was moving with 5.84 m/s just after the collision. And the Car A was moving with 4.42 m/s just before the collision .

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