Question

Mrs. Waid drives her car up Route 8 at 80mph. If her car weighs 2500 lbs,

how much Kinetic energy does it have?

Answer 1

1.358 J is the kinetic energy of the car driven by Mrs. Waid.

Step-by-step explanation:

Given data:

Velocity at which Mrs. Waid drives her car = 80 mph

In order to convert mph (meter per hour) into mps (meter per second),

`(80)/(3600)=0.0222 \mathrm{m} / \mathrm{s}`

Car weighs 2500 lbs, means mass of the car, m = 2500 lbs

I kilo gram = 2.20462 pound

Therefore, 1 pound (lb)= 0.45359237 kilograms (kg).

To converting pounds into kilogram,

`(2500)/(0.45359237)=5511.55 \mathrm{kg}`

As we know, the kinetic energy can be defined as directly proportionate to the object’s mass (m) and square of its velocity (v). The expression can be given as below,

`\text { kinetic energy }(K . E)=(1)/(2) * m * v^(2)`

By substituting the given values, we get

`\text { kinetic energy }(K . E)=(1)/(2) * 5511.55 * 0.0222^(2)`

`\text { kinetic energy }(K . E)=(1)/(2) * 5511.55 * 0.00049`

`kinetic energy (K . E)=1.358 joule`