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planauts
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Homework Statement
The stoplight had just changed and a 2000 kg Cadillac had entered the intersection, heading north at 3.0 m/s, when it was struck by a 1000 kg eastbound Volkswagen. The cars struck together and slid to a half, leaving skid marks angled 35 degrees north of east. How fast was the Volkswagen going just before the impact?
Homework Equations
The Attempt at a Solution
So basically what I did was divided into components.
x: (3)(2000) = (3000)*v_x
y: (v_vw)*(10000) = (3000)*v_y
v_x, v_y is the velocity (after collision) in the x and y direction, respectively, of both cars stuck together (since it is an inelastic collision).
v_vw is the initial velocity of the Volkswagen.
Now what I did was that the angle is 35 degrees north of east. So basically made a triangle and figured that tan(35) = (v_y)/(v_x). This means (v_x)*(tan35) = v_y.
Then, I simplified the component equations to get:
x: 2 = v_x
y: v_vw = 3*v_y
Then plugging in for v_y, I got: v_vw = 3(2)(tan35) = 4.2 m/s as the velocity of the volkswagen.
However, the answer key says 8.6 m/s. Could someone please help me out?
Thanks