Average Speed Calculation for a Car Accelerating from Rest

What is the average speed of a car accelerating from rest to 20 m/s in the first minute and then to 40 m/s in the next minute?

During this 2-minute period, what is the average speed of the car?

Answer:

The average speed is 20 m/s.

When a car accelerates from rest to a speed of 20 m/s in the first minute and then accelerates further to a speed of 40 m/s in the next minute, the average speed can be calculated by determining the total distance traveled over the total time elapsed.

During the first minute, the average speed of the car is the average of 0 m/s (initial speed) and 20 m/s (final speed), resulting in an average speed of 10 m/s. The distance covered in the first minute is calculated as 10 m/s * 60 s, which equals 600 m.

In the second minute, the average speed is the average of 20 m/s (initial speed) and 40 m/s (final speed), resulting in an average speed of 30 m/s. The distance covered in the second minute is then calculated as 30 m/s * 60 s, which equals 1800 m.

Therefore, the total distance covered over the 2-minute period is 600 m + 1800 m, equaling 2400 m. With a total time of 120 seconds, the average speed is determined by dividing the total distance by the total time, resulting in an average speed of 20 m/s.