Question

The fastest auto race in the United States is the Busch Classic at Daytona. In 1987, the winner's average speed was about 318 km/h. If the kinetic energy of the winning car was 3,800,000 J, what was the mass of the car and its driver?

a. 239.25 kg
b. 119.63 kg
c. 478.50 kg
d. 957.00 kg

Answer 1

The mass of the car and its driver is approximately 119.63 kg.

Step-by-step explanation:

To find the mass of the car and its driver, we can use the formula for kinetic energy:

KE = (1/2)mv²

Where KE is the kinetic energy, m is the mass, and v is the velocity. Rearranging the formula, we can solve for mass:

m = (2KE)/(v²)

Plugging in the values given, we have:

m = (2 * 3,800,000 J) / (318 km/h)²

Converting km/h to m/s, we have:

m = (2 * 3,800,000 J) / ((318 km/h * (1000 m/km))/(3600 s/h))²

Simplifying, we get:

m = 119.63 kg

Therefore, the mass of the car and its driver is approximately 119.63 kg.