If a 1000 kg car accelerates from rest to a speed of 20 m/s in 10 seconds, what is the average power output of the car's engine?
Practice Questions
1 question
Q1
If a 1000 kg car accelerates from rest to a speed of 20 m/s in 10 seconds, what is the average power output of the car's engine?
2000 W
4000 W
6000 W
8000 W
First, calculate the work done: W = 0.5 * m * v^2 = 0.5 * 1000 kg * (20 m/s)^2 = 200000 J. Then, power is P = W/t = 200000 J / 10 s = 20000 W.
Questions & Step-by-step Solutions
1 item
Q
Q: If a 1000 kg car accelerates from rest to a speed of 20 m/s in 10 seconds, what is the average power output of the car's engine?
Solution: First, calculate the work done: W = 0.5 * m * v^2 = 0.5 * 1000 kg * (20 m/s)^2 = 200000 J. Then, power is P = W/t = 200000 J / 10 s = 20000 W.
Steps: 10
Step 1: Identify the mass of the car, which is 1000 kg.
Step 2: Identify the final speed of the car, which is 20 m/s.
Step 3: Identify the time taken to reach that speed, which is 10 seconds.
Step 4: Use the formula for work done (W) when accelerating: W = 0.5 * m * v^2.
Step 5: Substitute the values into the formula: W = 0.5 * 1000 kg * (20 m/s)^2.
Step 6: Calculate (20 m/s)^2, which is 400 m^2/s^2.
Step 7: Multiply 0.5 * 1000 kg * 400 m^2/s^2 to get W = 200000 J.
Step 8: Use the formula for power (P): P = W / t.
Step 9: Substitute the values into the power formula: P = 200000 J / 10 s.
