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## Homework Statement

A 1500kg sedan travelling from north to south is struck by a 2200kg truck that is travelling from east to west. The two vehicles become enmeshed due to the impact and slide thereafter. Measurements show the coefficient of friction between the tires and the road is 0.75. The two vehicles slide 5.39m west and 6.43m south of the point of impact. How fast was each vehicle traveling just before the collision?

## Homework Equations

P1x = P2x

P1y = P2y

P1x: mx*V2x = V2*(mx + my)

P1y: my*V2y = V2*(mx + my)

P1x = mx*Vt

P1y = V2*(my + mx)

P1y = my*Vy

Ffriction(x) = m(s + t)*a

Ffriction(y) = m(s + t)*a

a = g*μ

V2x = (-2*ax*xskid)^(1/2)

V2y = (-2*ay*yskid)^(1/2)

## The Attempt at a Solution

mx*V1x = V2y*(mx + my)

V2y = (2*9.8*0.75*6.43)^(1/2) = 9.722...m/s

V2x = (2*9.8*0.75*5.39)^(1/2) = 8.901...m/s

Now I will substitute V2y and V2x into the conservation of momentum equation:

my*V1y = V2y*(mx + my)

Isolating V1y = (9.722...m/s*3700kg)/1500kg = 23.98...m/s which is wrong because the textbook's answers are 12m/s and 21m/s. I get V1x = 14.97...m/s. Both are wrong by 3m/s, but I have no idea why.

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