Karleen Brown

New AP Physics teacher. All online. Always awesome.

[Karleen Brown @MrsBrownTPS]

@JacobsPhysics Yes, thank you! :)

[Karleen Brown @MrsBrownTPS]

@JacobsPhysics I worked myself into a tizzy about this today with Atwood Machines. The acceleration of each block should be the same for a massless/frictionless pulley with massless string, correct? 1/4

[Karleen Brown @MrsBrownTPS]

BUT! If you look at the two-block system, you DO have an acceleration on the system... What on Earth am I missing?! How can you have a net acceleration of zero on the COM yet a no zero acceleration on the system? 4/4

[Karleen Brown @MrsBrownTPS]

So! Here is my conundrum: if the acceleration up equals the acceleration down the net acceleration of the system should be zero, correct? Which means the acceleration of the COM of the system is also zero. 3/4

[Karleen Brown @MrsBrownTPS]

@bwilliams025 @JacobsPhysics A gamble that paid off 👍🏻

[Karleen Brown @MrsBrownTPS]

The first Monday after class ended had me like...

[Karleen Brown @MrsBrownTPS]

@SaraTulchinsky @JacobsPhysics The force of friction to push Miss Ladybug forward would directed through the COM and would not cause a torque that would change angular velocity. Unlike the sideways friction, which does cause a torque.

[Karleen Brown @MrsBrownTPS]

This is amazing! If you haven't looked at the art of @aldescery then you are missing out!

[aldescery ❆⁷ 🎗️ @_aldescery]

@JacobsPhysics

@MrsBrownTPS's student's drawing of @Ednathehippo redone!

Edna, Bertha and Anthony enjoy some lakeside fun :D

[Karleen Brown @MrsBrownTPS]

@JacobsPhysics Asked my students about this today. One was *dead set* on writing. He confessed today that he will be typing his answers because it is more efficient than how he could think to upload a picture. Needless to say, the class was FLOORED! XD

[Karleen Brown @MrsBrownTPS]

@JacobsPhysics I know some of my students use the Notes app on their iPhone to take crisp scans of their work and AirDrop it as a pdf to the computer for their homework this year. They say it works really nicely. I want to ask them tomorrow in class how this was working for them in the Demo.

[Trevor Packer @AP_Trevor]

Learn what open book/open notes means, what you can and can't do on the internet, and what we're doing to ensure fairness on this year's AP Exams. https://t.co/YVt4u3qzcq

[Karleen Brown @MrsBrownTPS]

Yep. What he said.

[JacobsPhysics @JacobsPhysics]

If you're still working under 5 minutes left, it's not worth it! Yes, maybe you might manage one more point - maybe not. But you risk a ZERO if you don't submit in time! No pity, no remorse, no exceptions!!! @MrJBphysics

[Karleen Brown @MrsBrownTPS]

@JacobsPhysics @MrJBphysics @dog_rates What if it happens to be Edna fan-art at your table though? :P

[Karleen Brown @MrsBrownTPS]

@MrJBphysics @JacobsPhysics @dog_rates I shiver at the thought - considering how many of my students have done this in class this year :|

[Karleen Brown @MrsBrownTPS]

@Ednathehippo Another one of my students drew you pretending to be a shark in one of @JacobsPhysics example problems. This would be fun to see @aldescery 's interpretation!

[JacobsPhysics @JacobsPhysics]

Thank you, @MrJBphysics - folks, I'm not the only one saying "take a deep breath". If you're panicking, you're doing it wrong! Relax and let your physics knowledge show! Control only the things you can control! Your worth is not defined by your AP score, anyway!

[Karleen Brown @MrsBrownTPS]

@MrJBphysics Yes, thank you! Can’t wait to show my class the discussion on Monday! Thank you for the great videos. My students (and I!) have enjoyed them.

[Karleen Brown @MrsBrownTPS]

@MrJBphysics My class wants you to settle an argument. In rotational motion, is the translational velocity for a point some distance from the COM the same as saying tangential velocity?

[Karleen Brown @MrsBrownTPS]

@bwilliams025 @JacobsPhysics This is where the discussion in class started going down a confusing rabbit hole for some! 😂 So, to clarify, it can refer to the velocity of the point some distance away from COM, but in a special case (rolling without slipping) it can refer to the translational velocity?

[Karleen Brown @MrsBrownTPS]

@JacobsPhysics My class was discussing translational versus angular velocity. Is the v=rw equation referring to the velocity of the pt some distance away from the axis of rotation, or is it changing the furthermost rotational velocity to the translational velocity of the COM?