Question

A toy plane with a mass of 20 kg is flying at 10 m/s. What is its kinetic energy?

A. 1 000 J
B. 200 J
C. 2 000 J
D. Cannot be determined

Answer 1

A

On edg. ‘1,000 j’ hope it helps !:)

Answer 2

`\boxed {\boxed {\sf A. \ 1000 \ Joules}}`

Step-by-step explanation:

Kinetic energy can be found using the following formula.

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

where m is the mass and v is the velocity.

The mass of the toy plane is 20 kilograms and the velocity is 10 meters per second.

`m= 20 \ kg \\v= 10 \ m/s \\`

Substitute the values into the formula.

`E_k=(1)/(2)(20 \ kg) (10 \ m/s)^2`

Solve the exponent first.

• (10 m/s)²= 10 m/s *10 m/s= 100 m²/s²

`E_k=(1)/(2) (20 \ kg) (100 \ m^2/s^2)`

Multiply the last two numbers together.

`E_k= (1)/(2)(2000 \ kg*m^2/s^2)`

Multiply by 1/2 or divide by 2.

`E_k= 1000 \ kg*m^2/s^2`

• 1 kilogram square meter per square second is equal to 1 Joule.
• Our answer of 1000 kg*m²/s² is equal to 1000 Joules

`E_k= 1000 \ J`

The kinetic energy of the toy plane is 1000 Joules