– Good morning. Did you know that velocity measurements depend on the frame of reference from which they are taken? – Hey guys?
– Hey Bo. – Hi Bo. ^♫ Flipping Physics ♫ – In other words, the motion of the person taking the measurements will affect the interpretation of the motion of the object being observed. – Uh what? – (chuckling) All right, I’ll try again. Let’s try showing a classic example. A guy riding a skateboard tosses a ball up in the air. From the perspective, or frame of reference, of a stationary bystander, the ball appears to follow a parabolic curve. However, from the perspective, or frame of reference, of the guy moving on the skateboard, the ball appears to move straight up and down. In other words, two observers, moving with respect to one another,
will usually disagree on the description of the motion of an object. To put it one more way, all motion is relative to the observer’s view point, or what we call the observer’s frame of reference. Thank you very much for learning with me today, I enjoyed learning with you. – Can we please see those again? – Uh yeah, please? – Sure, I’ll add another example, dropping a ball from a moving car. And I’ll add some music. (acoustic guitar music) ♫ Until I see ♫ The daylight in your arms ♫ And you’re starting fires in my home ♫ The daylight in your arms ♫ And you starting fires in my home – I didn’t get to say anything in this video. ♫ Until I see ♫ The daylight in your arms

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1. Flipping Physics says:

A classic frame of reference example; riding a skateboard and throwing a ball.  Thank you very much Chris Dupont for letting me use my recording of your show at The Ark in this video.  #PhysicsED #flipclass

2. Samuel Bean says:

LOVE that last line!

3. AyalaMrC says:

Very well done, as usual.  Far more updated than what I've used in my classes in the past: Frames of Reference (1960) Educational Film (although I dearly love that old film)

4. Nancy Chang says:

Thank you! This really helped me in understanding different perspectives of motion. Great video shots and visual explanations 😀

5. Alexandra Hopkins says:

Great! It was great to see the parabola forming right before my eyes. And enjoyed the humor! The only thing that I don't get is why all the students look like the professor. How do you do that?

6. The AlterNatives says:

Great learning tool for my homeschooler! Thanks so much!

7. Aman Rubey says:

this is what I wanted

8. Oscar Treu says:

i love this video <3 realy good jobs!!!!!

9. King G says:

tanks dweude

10. John Phillips says:

Gold. Thanks mate.

11. AyalaMrC says:

If you've never seen the 60s science film Frames of Reference, you should take the time to. It has the predecessor to the gopro and some awesome segments with fictitious forces. https://www.youtube.com/watch?v=uMN4L94O4HE&index=4&list=PL6Pw5RXSrjGPVsyEM-brAhRp3w66Coh01

12. Ghost Zêno says:

This is terrible stop

13. Lance Kane says:

Watch those wrist rockets!!!,!

14. Priyanka Goyal says:

You are awesome there guy

15. Kalman Laslo says:

wow

16. SlickRick4EVER says:

I hope no other skateboarder sees this, but u just gave a HUGE secret to skateboarding. 😎🤙

17. Johnny says:

I mean the ball IS going up and down AND at a parabolic curve. So even if I'm skating and throwing the ball up, I acknowledge that if I throw the ball up at one point, I'm still catching it at another point cause both me and the ball is going –> at the same speed.