a 2000 kg truck is traveling south, a sports car is traveling west. they become entangled in a collision and leave a skid mark that is 20 meters long in a direction 14 degrees to the west of the direction of travel of the truck. Coefficient of sliding friction between tire and road is 0.6. what are the original velocities of both cars?(adsbygoogle = window.adsbygoogle || []).push({});

I have found three equations with three unknowns and I can solve for all three velocities, but I do not need to know the coefficient of friction and I do not need to know that the the skid mark is 20 meters long.

m1=2000kg

v1=initial velocity of truck

m2=1000kg

v2=initial velocity of car

m3=3000kg

v3=final velocity of both vehicles

equation 1, total momentum of system:

[tex] m_1v_1+m_2v+2 = m_3 v_3[/tex]

equation 2, momentum in y direction of system:

[tex] m_1v_1= m_3 v_3 cos(14)[/tex]

equation 3, momentum in x direction of system:

[tex] m_2v_2= m_3 v_3 sin(14)[/tex]

my question is, if I solved these equations as a matrix, would this give me the original velocities of both cars? I am wondering this because I did not use the coefficient of friction nor did I use the 20 meters long skid mark. I was wondering if this method works. thanks!

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# Homework Help: Final velocity of both vehicles

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