Question

A car moving with a velocity of 20 meters/second has 1.8 × 105 joules of kinetic energy. What is the mass of the car?

A.) 4.6 × 102 kilograms

B.) 9.0 × 102 kilograms

C.) 1.0 × 103 kilograms

D.) 1.2 × 103 kilograms

Answer 1

The answer would be B

Answer 2

Answer: The correct answer is
`m=9.0* 10^(2) kg`.

Step-by-step explanation:

The expression for the kinetic energy is as follows;

`KE=(1)/(2) mv^(2)`

Here, m is the mass of the object and v is the velocity.

It is given in the problem that A car moving with a velocity of 20 meters/second has
`1.8* 10^(5) J` of kinetic energy.

Calculate the mass of the car by rearranging the above expression.

`m=(1)/(2) (KE)v^(2)`

Put
`KE=1.8* 10^(5) J` and v= 20 m/s.

`m=9.0* 10^(2) kg`

Therefore, the correct option is (B).