What if everyone jumped?
Category: Analysis
Suppose everyone in the world got together and jumped. Would the Earth move? Yes. Would it be noticeable? Time for a calculation.
Posted by Rhett Allain at 3:48 PM • 14 Comments • 0 TrackBacks
Dot Physics
What happens when you take some basic, introductory physics and apply them to cool things you see? Dot Physics happens. This blog looks at movies, experiments, demos and other topics typically aimed at the introductory physics level.
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Rhett Allain is an Associate Professor of Physics at Southeastern Louisiana University. He
enjoys teaching and talking about physics. Sometimes he takes things apart and can't
put them back together.
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calculation:
Wolfram Alpha Widgets
Category: calculation
So, how about I just give a quick review of some different ways to do this. For all these methods, I will put in a calculator to determine the density of something given its mass and volume.
Posted by Rhett Allain at 10:38 PM • 4 Comments • 0 TrackBacks
Black Dress: chance or conspiracy?
Category: calculation
Anyway, my first comment was: "Wow, everyone is wearing black. Was this a planned event or was black part of the dress code?" The response was that it was just pure chance that all the women were wearing black. ALL CHANCE?
Posted by Rhett Allain at 2:45 PM • 18 Comments • 0 TrackBacks
How many bullets did the commando shoot?
Category: Analysis
The myth for this particular clip was that guns never run out of ammo in the movies. Right away, I thought: I wonder how many bullets he shot? BRING IT ON.
Posted by Rhett Allain at 10:10 PM • 12 Comments • 0 TrackBacks
How far will the car go?
Category: acceleration
Actually, I will just make a projectile motion spreadsheet. That way, anytime you want to do a projectile motion problem, you can come here. Maybe this is a bad idea, but I am going to do it anyway.
Posted by Rhett Allain at 12:02 PM • 3 Comments • 0 TrackBacks
How big of a balloon do you need to get to 120,000 feet high?
Category: Analysis
I am still thinking about the Red Bull Stratos Jump. Sorry, but there is just tons of great physics here. Next question - how big of a balloon would you need to get up to 120,000 feet?
Posted by Rhett Allain at 5:41 PM • 3 Comments • 0 TrackBacks
Star Trek Space Jump
Category: acceleration
But really, is this a spoiler alert if it is from the trailer of a movie that has been out forever? Of course, I talking about the latest Star Trek movie where three guys jump out of a shuttle and into the atmosphere.
Posted by Rhett Allain at 2:54 PM • 9 Comments • 0 TrackBacks
Oil Spill Estimation
Category: Analysis
How exactly do you estimate the amount of oil flowing into the gulf?
Posted by Rhett Allain at 6:23 PM • 8 Comments • 0 TrackBacks
Big spaceships with even bigger thrusters
Category: acceleration
One of the things I always think is interesting is to consider objects of different size. Perhaps the general idea is that you can just scale stuff up or down as you like. But, it doesn't work this way. Let me start with my own spaceship. It is a sphere with a thruster on the back.
Posted by Rhett Allain at 2:39 PM • 44 Comments • 0 TrackBacks
Oak Trees are awesome
Category: Analysis
Look how far those limbs extend horizontally. That branch is about 12 meters long. Why is this amazing? Have you ever tried to hold an 8 foot 2 x 4 board horizontally by holding one end?
Posted by Rhett Allain at 8:00 AM • 15 Comments • 0 TrackBacks
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