A 833 kg automobile is sliding on an icy street. It collides with a parked car which has a mass of 561 kg. The two cars lock up and slide together with a speed of 16.8 km/h. What was the speed of the first car just before the collision?

The speed of the first car just before the collision is 7.841 m/s.

Explanation:

Given that,

Mass of the automobile, m = 833 kg

Mass of the parked car, m' = 561 kg

The final speed of the cars lock up and slide together with a speed of 16.8 km/h, V = 16.8 km/h = 4.67 m/s

If two cars lock up and slide together, then it is the case of inelastic collision. The momentum will remains conserved such as :

v is the speed of the first car

v' is the speed of the second car that is at rest

So,

So, the speed of the first car just before the collision is 7.841 m/s. Hence, this is the required solution.

increase masses, decrease separation