A 2000 kg police car going 15.5 m/s rear-ends a 1500
Le car going 15.5 m/s rear-ends a 1500 kg sedan moving at 2.0 m/s. After the collision the
two cars move together as one unit.
i.
ii.
iji.
calculate the momentum of the police car before the collision
calculate the momentum of the sedan before the collision
what is the total mass of the sedan and the police car
What velocity do they move with after the collision _
iv.

i. 31000 kg.m/s

ii. 3000 Kg.m/s

iii. 3500 Kg

iv. 9.71 m/s

Explanation:

i.

Momentum, p= mv where m is the mass of the object and v is the velocity of the same object

Substituting m for 2000 Kg then v for 15.5 m/s then the momentum of the police car before collision will be

p=2000*15.5= 31000 kg.m/s

ii.

Momentum, p= mv where m is the mass of the object and v is the velocity of the same object

Substituting m for 1500 Kg then v for 2 m/s m/s then the momentum of the police car before collision will be

p=1500*2= 3000 kg.m/s

iii.

Total mass of cars will be 2000+1500= 3500 Kg

iv.

From the law of conservation of momentum, the sum of initial momentum equals the sum of final momentum

Momentum, p=mv where m is the mass and v is the velocity

where is the common velocity, and are velocities of 2000 Kg police car and 1500 Kg sedan car respectively, and are masses of 2000 Kg police car and 1500 Kg sedan car respectively