Recent content by supernova88

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    Velocity to land 1/4, 1/2, and around Earth

    Thanks, BvU, I'm starting to think I'm over reaching with this problem and, yes, making too many assumptions. However now I just want to know what the right answer is for myself. Thanks for the insight that g is tangential!
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    Velocity to land 1/4, 1/2, and around Earth

    So I just realized the error in my thinking ... orbits don't take 50 seconds! I'm still curious for some simple ways to find the velocity it takes to land 1/4, 1/2, and 1 whole circle around the Earth. Thanks.
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    Velocity to land 1/4, 1/2, and around Earth

    Hi, I'm actually a teacher presently undergoing gravitation and circular motion with my students, and ran into a problem I forgot how to think through. I'm trying to explain Newton's cannonball thought process (shoot a cannonball fast enough off a mountain and it will circle the earth), and...
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    Preparing for High School Physics Final Exam

    I presently teach physics to high school sophomores and we are spending the entirety of this upcoming week preparing for the final exam. However, many of my students have "checked out" and are resistant to working or studying. Review packets and problems only seem to inspire a small few...
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    Making sense of distance and speed of expanding universe

    I'm trying to reconcile the fact that regions of the universe are expanding faster than light, and that as a consequence the observable universe is far more than 13.7 billion light years across. I trust these are the facts, but I'm stuck figuring out how we know these to be true. I feel like...
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    How to explain the curvature of space-time to students

    I teach a class on astronomy and recently tried to explain the curving of space time by massive objects like neutron stars and black holes. I even used a sheet of spandex to represent space-time which we bent using different weights. However my students were very confused how space, which they...
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    Explaining usefullness of displacement and velocity

    To be more specific, A.T., I'm trying to explain displacement/velocity to people who've never heard of them before. Because these kids don't yet know anything about energy and work, I'm trying to keep things simple, but I'm struggling to find everyday examples to point to. I could, for...
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    Is nuclear fusion reverse entropy?

    If you look up a diagram or illustration for the process of fusion, as seen in the sun for instance, you'll see that it's not just two particles coming together and that's that. Fusion also releases energy in the form of neutrinos, positrons, photons, etc. Furthermore, the process doesn't stop...
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    Explaining usefullness of displacement and velocity

    I know the difference between distance and displacement, and speed and velocity, but I'm struggling how to explain the usefulness of displacement and velocity in the real world? For instance, our cars count the distances they travel, not displacement as one might see on a map, while airplanes...
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    Why Is Average Velocity Calculated Differently in Various Scenarios?

    Thanks for all the help. I thought I understood where I was confused but I needed some confirmation.
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    Why Is Average Velocity Calculated Differently in Various Scenarios?

    I'm trying to understand the kinematic equations well enough to explain to someone else, but the analogies I've come up with don't seem to be working well. 1) If a car travels 25 km/h for a certain distance, turns around in the opposite direction, and then turns back on its original path yet...
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    Why do Van de Graaff generators produce such low current?

    I'm currently in a program to be a physics teacher and for an upcoming mock lesson plan I am going to show the scene from Jurassic Park where the kid gets blasted off the electric fence and talk about if it is realistic. To supplement my discussion I'll be using a Van de Graaff generator to...
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