Question

A car moving with a velocity of magnitude 20 m/s has a momentum of 5000 kg-m/s. Which of these will be the mass of the car? O10000 kg O 5000 kg O 2500 kg O 250 kg​

Answer 1

Answer:

The work done is the same as the amount of energy increase. The formula for kinetic energy is 12mv2 .

The initial KE of the car is 12(1000)×202=200,000 joules.

The final KE of the car is 12(1000)×302=450,000 joules.

The difference between these is the amount of work done: 450,000−200,000=250,000 joules.

Answer 2

Given: A car moving with velocity of magnitude 20 m/s has a momentum of 5000 kg-m/s.

To find: Mass of the car

Explanation: Momentum is the product of mass and velocity of the object.

Momentum (p)= 5000 kg-m/s

Velocity(v)= 20 m/s

Let mass of car be m.

Momentum= Mass of car * Velocity of car

=> 5000 = 20* m

=> m = 5000/20

= 250 kg

Therefore, the mass of the car is option (d) 250 kilograms.