Brianno Coller

Professor of Mechanical Engineering, part-time game developer.

[Brianno Coller @BriannoColler]

30 minutes past midnight. Laugar, Iceland.

[Brianno Coller @BriannoColler]

@Dreami_Killer The answer is C. The two identical disks are spinning at the same rotation rate, but in opposite directions. The combined angular momentum is zero in the end.

[Brianno Coller @BriannoColler]

Traumatized tonight, hearing the news from Michigan. 15 years ago, tomorrow, a gunman opened fire in a classroom on my campus, Northern Illinois Univ, killing 5, injuring 21, leaving an indelible emotional scar on the rest of us. So sad. So infuriating.
We love you MSU. So sorry

[Brianno Coller @BriannoColler]

@DarekDewey That's great!

[Brianno Coller @BriannoColler]

@rjallain You have to be careful. When you have an accelerating body (the wheel) that's rolling without slip, the friction is going to play an important role. It can't just be waived away. (Back wheel too.) There are configurations for which friction is larger than applied force.

[Brianno Coller @BriannoColler]

@MetaAI It keeps trying to steer the conversation back to cheese!

[Brianno Coller @BriannoColler]

@con_sut This is me. I took this picture. Why do you have a picture of me as your profile pic?

[Brianno Coller @BriannoColler]

@POTUS Feb 14, 2018, was also the tenth anniversary of when a gunman killed 5 students and shot 17 more in a classroom at Northern Illinois University. So tragic

[Brianno Coller @BriannoColler]

@anaismitchell Going on a long road trip and navigating with the Rand McNally Atlas.

[Brianno Coller @BriannoColler]

@boomsupersonic On-board waffle maker.

[Brianno Coller @BriannoColler]

@boomsupersonic EZ Pass transponder

[Brianno Coller @BriannoColler]

@AlmaKraken @ChiMarathon Email this morning said I was not selected.

[Brianno Coller @BriannoColler]

@MrJoeMilliano To explain why forces between ladybug and disk are in opposite directions and still consistent with everything else, recall the Coriolis component of acceleration in polar coordinates. My explanation is below. Explanation of Coriolis is here: https://t.co/WZCNS4x7BK

[Brianno Coller @BriannoColler]

@changandysu I don't know about AP standards, but I'm always frustrated when I have to re-teach FBDs to college sophomore engineering students. We draw the FBD for this problem like that shown below. Reasons are provided in the picture.

[Brianno Coller @BriannoColler]

@KimFreudenberg @msruggerio explained it well. I'll just add that I like to also roll a can with a more viscous fluid such as tomato sauce in it... and compare it to the can of broth. Because some of the sauce adheres to the can as it rolls rotational inertia increases.

[Brianno Coller @BriannoColler]

@McKaleDavis I'm surprised and impressed that the gel had such a big effect so quickly. I'm a newbie to this.

[Brianno Coller @BriannoColler]

@McKaleDavis I had a big fueling mistake at the Chicago Marathon today too. The big difference is that I'm a know-nothing 4+ hour marathoner who barely crawled across the finish line. Good for you for finishing strong.

[Brianno Coller @BriannoColler]

@ChiMarathon @BankofAmerica 6 river crossings, right?

[Brianno Coller @BriannoColler]

@HorizonNews @Cubs Ugh. This has nothing to do with angular momentum. Centripetal acceleration, yes. But not angular momentum.