A graph showing the kinetic energy of a ball over time is shown below. Which of the following statements best explains the relationship between the kinetic energy of the ball and its speed?
A.
The kinetic energy of the ball decreases as its speed increases.
B.
The kinetic energy of the ball remains the same as its speed increases.
C.
The kinetic energy of the ball increases as its speed increases.
D.
The kinetic energy of the ball increases over time as the ball travels at a constant speed.

(newtons first law)

conservation of momentum law states :

momentum before collision = momentum after collision

momentum p (kg-m/s)= mass * velocity

say moving car=1 000 kg, velocity = 10 m/s then p = 1 000*10= 10 000 kg-m/s

say still car = 2 000 kg, velocity = 0 m/s then p = 2 000* 0 = 0 kg-m/s

total momentum prior to collision = 10 000 + 0 = 10 000 kg-m/s

momentum after collision = 10 000 kg-m/s

mass now = 1 000 kg+2 000 kg = 3 000 kg

10 000 = 3 000 kg* velocity m/s

10 000/3 000 = velocity

3.33 m/s = velocity after collision

an impulse is a force applied over time , momentum is exclusive of external forces and a perfect collision is implied

yes the answer is total mass in unchanged   : )