Pariah Posted February 11, 2019 Author Report Share Posted February 11, 2019 44 minutes ago, novi said: Assuming standard physics word problem rules and constant forces, and not showing my work because I don't want to type in that many equations. And assuming I remember how significant digits work: 1. 6.563 x 10^6 J 2. 8.576 x 10^3 N 3. 6.43 x 10^5 W Yes, I got an A in AP Physics. Why do you ask? Excellent! Did you solve the problem by finding acceleration from the velocities, or did you use the Work-Energy Theorem? Quote Link to comment Share on other sites More sharing options...
Cancer Posted February 11, 2019 Report Share Posted February 11, 2019 FWIW, I have often given astrophysical situations in problems where the values invoked are way outside most people's experience. For instance, I'll be asking the students next quarter to compare the heat from Earth's accretion to that from its differentiation, and later (after they have read a useful reference) to the heat of radioactive decay over the 4.55 Gyr since accretion. The problems are easy (the first is just the gravitational binding energy of a uniform sphere of Earth's mass and radius; for the second I give them a core density and radius, and tell them the rest is in the mantle and give them that density) but unfamiliar. Later we'll do the conservation of angular momentum for the Earth-Moon system. Quote Link to comment Share on other sites More sharing options...
Old Man Posted February 12, 2019 Report Share Posted February 12, 2019 2 hours ago, Rails said: If you're going to drive 200+ mph, are you going to bother trying to stop at lights? Dude, I don't stop at lights now. Quote Link to comment Share on other sites More sharing options...
Old Man Posted February 12, 2019 Report Share Posted February 12, 2019 22 minutes ago, Cancer said: FWIW, I have often given astrophysical situations in problems where the values invoked are way outside most people's experience. And yet students come up with answers that are blatantly wrong anyway. Orbital velocities greater than c. Negative volume. And why can't they check the units?! Work is not measured in meters per second! Pariah 1 Quote Link to comment Share on other sites More sharing options...
Pariah Posted February 12, 2019 Author Report Share Posted February 12, 2019 21 minutes ago, Old Man said: And why can't they check the units?! Work is not measured in meters per second! This. This right here. Quote Link to comment Share on other sites More sharing options...
Pariah Posted February 12, 2019 Author Report Share Posted February 12, 2019 48 minutes ago, Cancer said: FWIW, I have often given astrophysical situations in problems where the values invoked are way outside most people's experience. I recently gave my students a conservation of momentum problem involving a U-238 atom that underwent alpha decay. Boy, were the results all over the place. Quote Link to comment Share on other sites More sharing options...
Badger Posted February 12, 2019 Report Share Posted February 12, 2019 1 hour ago, Old Man said: Dude, I don't stop at lights now. I wouldn't either, but the I'd plow into the 3 cars in front of me who decided to. Quote Link to comment Share on other sites More sharing options...
Badger Posted February 12, 2019 Report Share Posted February 12, 2019 42 minutes ago, Pariah said: I recently gave my students a conservation of momentum problem involving a U-238 atom that underwent alpha decay. Boy, were the results all over the place. The answer was 47. Quote Link to comment Share on other sites More sharing options...
Cancer Posted February 12, 2019 Report Share Posted February 12, 2019 44 minutes ago, Pariah said: I recently gave my students a conservation of momentum problem involving a U-238 atom that underwent alpha decay. Boy, were the results all over the place. Make it a beta-decay with an electron and a neutrino, and have them deduce which way the neutrino went from the post-decay velocity vectors of nucleus and electron. Quote Link to comment Share on other sites More sharing options...
Badger Posted February 12, 2019 Report Share Posted February 12, 2019 5 hours ago, Cancer said: Make it a beta-decay with an electron and a neutrino, and have them deduce which way the neutrino went from the post-decay velocity vectors of nucleus and electron. The number is 47. Quote Link to comment Share on other sites More sharing options...
Starlord Posted February 12, 2019 Report Share Posted February 12, 2019 9 hours ago, Pariah said: In my defense, I am a first-year Physics teacher. I'm used to dealing with things on a much smaller scale. That, and I was writing the problem as the tardy bell was ringing this morning. Let's see if any of my students catch the problem as well as you all did. Gold stars for everyone! Yes! My first gold star! Come to think of it...my very first star! Quote Link to comment Share on other sites More sharing options...
Starlord Posted February 12, 2019 Report Share Posted February 12, 2019 8 hours ago, Pariah said: I recently gave my students a conservation of momentum problem involving a U-238 atom that underwent alpha decay. Boy, were the results all over the place. What about a problem involving Illudium PU-36 that modulates space when exploding? Quote Link to comment Share on other sites More sharing options...
Bazza Posted February 12, 2019 Report Share Posted February 12, 2019 11 hours ago, Pariah said: In my defense, I am a first-year Physics teacher. I'm used to dealing with things on a much smaller scale. That, and I was writing the problem as the tardy bell was ringing this morning. Let's see if any of my students catch the problem as well as you all did. Gold stars for everyone! My first gold star for physics and I didn't do any work! Bonus! Quote Link to comment Share on other sites More sharing options...
novi Posted February 12, 2019 Report Share Posted February 12, 2019 13 hours ago, Pariah said: Excellent! Did you solve the problem by finding acceleration from the velocities, or did you use the Work-Energy Theorem? Um, Work-Energy Theorem? It's been... a while since I had a physics class, so I did a quick Wikipedia visit to make sure I had my formulas correct. And while I was all set to work out the acceleration, I then noticed the page mentioning that work is also equal to delta-Kinetic energy. Seemed like a much more straightforward and accurate approach. Pariah 1 Quote Link to comment Share on other sites More sharing options...
Logan D. Hurricanes Posted February 12, 2019 Report Share Posted February 12, 2019 2 hours ago, novi said: Um, Work-Energy Theorem? It's been... a while since I had a physics class, so I did a quick Wikipedia visit to make sure I had my formulas correct. And while I was all set to work out the acceleration, I then noticed the page mentioning that work is also equal to delta-Kinetic energy. Seemed like a much more straightforward and accurate approach. Teacher's pet! Quote Link to comment Share on other sites More sharing options...
Old Man Posted February 12, 2019 Report Share Posted February 12, 2019 Ugh. Triggered. Quote Link to comment Share on other sites More sharing options...
Badger Posted February 12, 2019 Report Share Posted February 12, 2019 One of these times, the answer will be 47. Quote Link to comment Share on other sites More sharing options...
Cancer Posted February 12, 2019 Report Share Posted February 12, 2019 13 hours ago, Starlord said: What about a problem involving Illudium PU-36 that modulates space when exploding? You can do that, but general relativistic spacetime lattice calculations are generally not found in undergraduate-level material, let alone high school. Quote Link to comment Share on other sites More sharing options...
Cancer Posted February 15, 2019 Report Share Posted February 15, 2019 Quote Oh, and on the homework ... remember how I talked about satanic questions? Problem 8 is a satanic question. See you Wednesday. Have a good weekend! Pariah 1 Quote Link to comment Share on other sites More sharing options...
Starlord Posted February 15, 2019 Report Share Posted February 15, 2019 , and problem 666 is about puppies! Quote Link to comment Share on other sites More sharing options...
Cancer Posted February 15, 2019 Report Share Posted February 15, 2019 Just think of the experiments we could run if we could get a reliable source for antipuppies! "PUPPY-ANTIPUPPY COLLISIONS AT 0.99c". Now there's some research! Logan D. Hurricanes 1 Quote Link to comment Share on other sites More sharing options...
Badger Posted February 15, 2019 Report Share Posted February 15, 2019 *calls PETA to Cancer's lab.* Quote Link to comment Share on other sites More sharing options...
Old Man Posted February 15, 2019 Report Share Posted February 15, 2019 *observes Cancer crashing PETA into each other at 0.99c* Pariah 1 Quote Link to comment Share on other sites More sharing options...
Pariah Posted February 16, 2019 Author Report Share Posted February 16, 2019 2 hours ago, Old Man said: *observes Cancer crashing PETA into each other at 0.99c* Tell me when the Kickstarter goes live. Quote Link to comment Share on other sites More sharing options...
Logan D. Hurricanes Posted February 19, 2019 Report Share Posted February 19, 2019 Ph.D. Student Breaks Down Electron Physics Into A Swinging Musical Quote A scientist just scored honors for a musical adaptation of his research on Friday. Pramodh Senarath Yapa, a physicist currently pursuing his doctorate at the University of Alberta in Edmonton, Canada, has been named the 2018 winner of the "Dance Your Ph.D." contest. The competition, sponsored by the American Association for the Advancement of Science (AAAS) and Science magazine, invites doctoral students and Ph.D. recipients to translate their research into an interpretive dance. The winner takes home $1000. It took Senarath Yapa six weeks to choreograph and write the songs for "Superconductivity: The Musical!" — a three-act swing dance depicting the social lives of electrons. The video is based on his master's thesis, which he completed while pursuing his degree at the University of Victoria in Canada. The 11-minute sing-songy rendition is far less paralyzing than the jargony title of Senarath Yapa's thesis alone: "Non-Local Electrodynamics of Superconducting Wires: Implications for Flux Noise and Inductance." Lucius 1 Quote Link to comment Share on other sites More sharing options...
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