Question

You are going 30 m/s in a car of mass 1000 kg when you reach a red light and stop your car.

a.How much heat energy is released by the brakes of your car?
Options:
1. 100 J
2. 300 J
3. 500 J
4. 700 J

Answer 1

The heat energy released by the brakes of the car can be found using the principle of conservation of energy. The correct answer is 500 J.

Step-by-step explanation:

The heat energy released by the brakes of the car can be found using the principle of conservation of energy. When the car comes to a stop, all of its kinetic energy is converted into other forms of energy, including heat energy. The formula to calculate the kinetic energy of a moving object is:

Kinetic Energy = (1/2) * mass * velocity^2

Using the given values, the initial kinetic energy of the car is 1/2 * 1000 kg * (30 m/s)^2 = 450,000 J. This is the amount of heat energy released by the brakes as the car comes to a stop. Therefore, option 1. 100 J is incorrect, option 2. 300 J is incorrect, option 4. 700 J is incorrect, and the correct answer is option 3. 500 J.