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rum2563
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Momentum Conservation --- so hard!
Two automobiles collide at an intersection. One car of mass 1.4 X 10^3 kg is traveling at 45km/h; the other car of mass 1.3 X 10^3 kg is traveling at 39km/h [E]. If the cars have a completely inelastic collision, what is their velocity just after collision?
v1m1 + v2m2 = v(m1 + m2)
Given information:
m1 = 1.4 X 10^3 kg
m2 = 1.3 X 10^3 kg
v1 = 45km/h --> 12.5 m/s
v2 = 39 km/h [E] --> 10.83 m/s
vf ' = ?
v1m1 + v2m2 = v(m1 + m2)
(12.5)(1.4 X 10^3) + (10.83)(1.3 X 10^3) = v (1.4 X 10^3 + 1.3 X 10^3 kg)
v = 11.7 m/s --> 42 km/H
But the answer that I get is wrong. So anyone please help me how to do this. Thanks.
The correct answer is 30 km/h.
Homework Statement
Two automobiles collide at an intersection. One car of mass 1.4 X 10^3 kg is traveling at 45km/h
Homework Equations
v1m1 + v2m2 = v(m1 + m2)
The Attempt at a Solution
Given information:
m1 = 1.4 X 10^3 kg
m2 = 1.3 X 10^3 kg
v1 = 45km/h
v2 = 39 km/h [E] --> 10.83 m/s
vf ' = ?
v1m1 + v2m2 = v(m1 + m2)
(12.5)(1.4 X 10^3) + (10.83)(1.3 X 10^3) = v (1.4 X 10^3 + 1.3 X 10^3 kg)
v = 11.7 m/s --> 42 km/H
But the answer that I get is wrong. So anyone please help me how to do this. Thanks.
The correct answer is 30 km/h.