In: Physics
A red car and a blue car are driving in the same direction on the interstate. The red car
is travelling at 25 m/s, while the blue car is travelling at 35 m/s. The driver of the blue
car is not paying attention and rear-ends the red car. The red car has a mass of 2,000
kg while the blue car is only 1,000 kg.
a. Prior to the collision, what is the value of the center of mass kinetic energy?
b. In order for this collision to be isolated, what is the maximum amount of energy
that can be converted to other forms during the collision? What percentage of
the initial kinetic energy does this represent?
c. If the system loses 40% of its kinetic energy in the collision, is the system
isolated? Why or why not?
d. Prior to the collision, how fast and in what direction would you need to be
travelling in order for the system to appear to have zero momentum?
e. Regardless of your answer to part (c), assume now that the two vehicles form
an isolated system. If they cars stick together, how fast will they be moving?
f. What minimum amount of kinetic energy must be conserved in order for this
system to be isolated?