Answer:
Speed of the 3,000-kg car before the collision = 7.41 m/s
Explanation:
Here momentum is conserved.
A 2,000-kg car moving east at 10.0 m/s collides with a 3,000-kg car moving north.
Initial momentum = 2000 x 10 i + 3000 x v j = 20000 i + 3000 v j
The cars stick together and move as a unit after the collision, at an angle of 48.0° north of east and at a speed of 5.98 m/s.
Mass = 2000 + 3000 = 5000 kg
Velocity = 5.98 cos 48 i + 5.98 sin 48 j = 4 i + 4.44 j
Final momentum = 5000 x (4 i + 4.44 j) = 20000 i + 22220 j
We have momentum is conserved
20000 i + 3000 v j = 20000 i + 22220 j
3000 v = 22220
v = 7.41 m/s
Speed of the 3,000-kg car before the collision = 7.41 m/s