Two cars collide at an intersection. Car A , with a mass of 2000 kg , is going f

Question

Two cars collide at an intersection. Car A, with a mass of 2000 kg , is going from west to east, while car B , of mass 1500 kg , is going from north to south at 17.0 m/s . As a result of this collision, the two cars become enmeshed and move as one afterward. 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 65.0 south of east from the point of impact. A) How fast were the enmeshed cars moving just after the collision? express answer in m/s B) How fast was car A going just before the collision? Express answer in m/s

Explanation / Answer

Solution :

For Car A:
p=mv
p=2000*u Ns (use u as velocity so there is no confusion later on)
For Car B:
p=mv
p=1500*17
p=25500 Ns
For Enmeshed Cars:
m=1500+2000
m=3500kg
p=mv
p=3500*v Ns
Resolve Vectors:
theta=65 degrees
Adjacent=2000*u
Opposite=25500
Hypotenuse=3500*v

A)How fast were the enmeshed cars moving just after the collision?

sin(theta)=O/H
sin(65)=25500/(3500*v)
v=25500/(3500*sin(65))
v=8.54m/s
The enmeshed cars are moving at 8.54 m/s.

B) How fast was car A going just before the collision?
tan(theta)=O/A
tan(65)=25500/(2000*u)
u=25500/(2000*tan(65))
u=7.81m/s
Car A is moving at 7.81 m/s, just before the collision.

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.