What Is the Difference Between Average Speed and Average Velocity?

AI Thread Summary
Average speed is calculated by dividing the total distance traveled by the total time taken, resulting in 3.95 m/s for the jogger's eight laps. However, average velocity considers displacement, which is zero since the jogger returns to the starting point after completing the laps. Therefore, the average velocity is 0 m/s, as it is defined as displacement divided by time. The distinction between average speed and average velocity is crucial in physics. Understanding these concepts helps clarify motion analysis in various scenarios.
sprinter08
Messages
18
Reaction score
0

Homework Statement



A person jogs eight complete laps around a 400m track in a total time of 13.5 minutes. Calculate, in m/s the average velocity.



Homework Equations





The Attempt at a Solution



I thought that I knew how to do this, but I think I just figured out the average speed. This is what I did:

400x8= 3200m

13.5/1 x 60sec./1 min= 810 seconds

3200m divided by 810 sec.= 3.95 m/sec
 
Physics news on Phys.org
At the end of the eight laps the person is where they started, so the final displacement is 0. Since velocity is defined as displacement divided by time, time is irrelevant, and the average velocity is 0 also.

You're correct, you've calculated the average speed.
 
Thank you!
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'A bead-mass oscillatory system problem'
I can't figure out how to find the velocity of the particle at 37 degrees. Basically the bead moves with velocity towards right let's call it v1. The particle moves with some velocity v2. In frame of the bead, the particle is performing circular motion. So v of particle wrt bead would be perpendicular to the string. But how would I find the velocity of particle in ground frame? I tried using vectors to figure it out and the angle is coming out to be extremely long. One equation is by work...
Back
Top