Timed quiz. Calculate the velocity of the pink car.
A. 20 m/s
B. 0.5 m/s
C. 1 m/s
D. 15 m/s

Option A

20 m/s

Explanation:

From the law of conservation of linear momentum, the sum of momentum before and after collision equals zero hence for this case also, the sum of momentum of the two cars before collision should be equal to momentum after collision.

Momentum is given as the product of mass and velocity, where velocity considers the direction. Momentum, p=mv where m is the mass of the object and v is the velocity.

Momentum before collision

Since the velocities of both cars before collision are zero hence their momentum are zero ie 0.5*0+(1*0)=0

Momentum after collision

For 0.5 Kg car, its momentum will be 0.5*-40=-20 Kg.m/s

For the 1 kg car its momentum will be 1*v=1v

v-20=0

v=20 m/s

where’s the list ? the question is incomplete

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.