Average Power Delivered by a Car Engine - Example Problem

The video tutorial explains the physics of a car engine's power output, focusing on a Prius accelerating from rest. It covers the conversion of velocity units, the calculation of average power, and the impact of drag force. The tutorial uses equations for power and force, and introduces a humorous analogy comparing engine power to horses, highlighting the environmental impact of energy use. The video concludes with a comparison of different acceleration scenarios, emphasizing the increased energy consumption required for faster acceleration.

What is the initial velocity of the car in the given problem?

• 9.25 km/h

• 42 km/h

• 0 km/h

• 3.0 km/h

Why is the drag force considered small in this problem?

• Due to the car's large size

• Because of the high air resistance

• Due to the car's low speed

• Because the car is very heavy

Which equation is used to calculate average power in this scenario?

• Power = Force x Velocity x cos(Theta)

• Power = Work / Change in Time

• Power = Mass x Acceleration

• Power = Force x Displacement

What is the angle Theta between the force applied and the displacement in this problem?

• 180 degrees

• 90 degrees

• 45 degrees

• 0 degrees

How much power in horsepower is developed by the engine?

• 5.5 horsepower

• 7.7 horsepower

• 10.2 horsepower

• 12.5 horsepower

What does pressing the 'horse pedal' metaphorically represent?

• Reducing fuel consumption

• Using more horsepower

• Increasing the car's speed

• Decreasing the car's weight

What happens when you press the 'horse pedal' further down?

• You use less energy

• You strap more metaphorical horses to the car

• The car's speed decreases

• The car becomes lighter

What is the new final velocity when the accelerator is pressed fully?

• 19 km/h

• 30 km/h

• 56 km/h

• 42 km/h

How much more energy is required to decrease the time of the event by 41%?

• 150% more energy

• 220% more energy

• 100% more energy

• 50% more energy

What is the original force applied by the engine in the problem?

• 800 Newtons

• 4040 Newtons

• 2000 Newtons

• 1270 Newtons