Question

I run around a circular track with a radius of 25 m for 4 and 1/4 times without stopping. It takes me 16 minutes. A) What is my speed? B) What is my velocity?

A. A) 4.9 m/s, B) 0 m/s
B. A) 7.81 m/s, B) 0 m/s
C. A) 4.9 m/s, B) 25 m/s
D. A) 7.81 m/s, B) 25 m/s

Answer 1

The speed of the person running around the circular track is 4.9 m/s, calculated by dividing the total distance by time. The velocity is 0 m/s because the final displacement is zero after completing the laps.

Step-by-step explanation:

You are asking about calculating speed and velocity for a person running around a circular track. Speed is a scalar quantity representing the rate of movement, while velocity is a vector quantity that includes both the speed and the direction of movement.

To calculate the speed, you need to know the total distance traveled and the time it took. The distance for one full lap around a circular track is the circumference, which is 2πr, where r is the radius of the circle. Since the radius is 25 m and you ran 4.25 laps, the total distance is 4.25 × 2π × 25 m. The time taken is 16 minutes, which is 960 seconds.

We use the formula speed = total distance/time to find the speed:

Speed = (4.25 × 2π × 25) / 960 ≈ 4.9 m/s

For velocity, because you end up at the starting point after running around the track, your displacement is zero, and since velocity is based on displacement, your velocity after 4.25 laps is 0 m/s.

Therefore, the correct answer to your question is A) 4.9 m/s, B) 0 m/s.