- #1
lioric
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Homework Statement
A 0.30 kg puck A, initially at rest on a frictionless horizontal surface, is struck by a 0.20 kg puck B
that is initially moving along the x-axis with a velocity of 2.0 m/s. After the collision, the 0.20
kg puck has a speed of 1.0 m/s at an angle of θ = 530 to the positive x-axis.
a) Determine the velocity of the 0.30 kg puck after the collision.
Homework Equations
total mommentum before collision + total momentum after collision
The Attempt at a Solution
total momentum before collision in x
puck A
0.2 x 2 = 0.4
puck B
0.3 x 0
total = 0.7kgm/s
total momentum before collision in y = 0 for all
Total momentum after collision x
puck A
0.2 x 1 x cos 53=0.12
puck B
0.3 x V x cos 53
Total =0.7kgm/s
Total momentum after collision y
puck A
0.2 x 1 sin 53 = 0.1597
puck B
0.3 x V x sin53
Total =0
Resolve in x for puck B
0.3 x V x cos 53
Let Vcos 53 = Vx
0.3 x Vx + 0.12 = 0.7
Vx = 1.93333m/s
Resolve in y for puck B
0.3 x V x sin 53
Let Vsin 53 = Vy
0.3 x Vy + 0.1597 = 0
Vy = -0.53
V2=Vx2 + Vy2
V2 = 1.933332+(-0.53)2
V=√4.02
v=2.005m/s
Is this right?