Posts

Apollo 13

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Weightlessness is an interesting concept but it is a concept that is easily misunderstood. Most people believe weightlessness to be when there is no force of gravity being applied to an object like when an object is far away from any other object, but that is not true. Weightlessness is when an object ONLY experiences the force of gravity. An example of what it feels like to be weightless is right after the highest point on a roller coaster when the coaster goes straight down and all the passengers lift out of there seats for a split second. In a more scientific and mathematical sense a perfect scenario is in any freefall problem where gravity is the only force.

An important factor in understanding weightlessness is understanding what weight is. Weight is not the force of gravity, instead weight is the normal force which is the force that the earth pushes up on someone. An example of the difference between the force of gravity and weight is if someone were to exert a force downwards …

Avengers: Infinity War

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Avengers is a classic superhero action movie with all of the classic superhero tropes, which means it is bound to have a bountiful supply of ridiculous physics. Today is only about Newton's three laws of motion, so there are a lot of things we are going to leave out but don't worry, there are still many scenes to talk about.

In this scene, Thor throws Stormbreaker into a bunch of goons and it keeps going without any decrease in speed. This violates Newton's first law in which an object in motion stays in motion unless acted on by an outside force. Sormbreaker does not slow down even after it chops dozens of goons that would produce a force against Stormbreaker.

Dr. Strange does this all the time so it might slip past you, but how does he levitate. According to Newton's second law F=ma, but Dr. Strange is levitating while gravity is acting on him and he also has mass, which means there should be a force pulling him down, but there is not. The only way for him to levita…

Armageddon

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Armageddon is an action movie with Bruce Willis which means it has to have perfect physics, well not quite, but it did pose an interesting question; What would we do if an asteroid was going to hit us? Well, NASA has you covered with a bunch of different techniques to prevent a true Armageddon.


First off, NASA is always on top of monitoring space to make sure that if an asteroid had a trajectory that would even come close to earth, they would investigate. To spot asteroids, many pictures are taken, more specifically, a few pictures are taken of a static shot of space a couple minutes apart, then a computer will scan for any moving objects. After an object is spotted the trajectory is calculated with the given data.

After that, there are many ways of dealing with an asteroid, but what I will be talking about is Asteroid Laser Ablation, which is basically shooting the asteroid with a really big laser. The whole purpose of the laser is to heat up part of the asteroid so hot that it turn…

Eraser

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In my opinion, Eraser is a typical action movie, and along with being a typical action movie, it has action movie physics, which don't always line up with the truth. In Eraser, the major plot device is a handheld railgun that shoots aluminum close to the speed of light (yes, I know this is ridiculous but just roll with it) and it is shot like any standard gun, but whoever is shot goes flying back.

c = Speed of Light = 2.998*10^8 m/s
vib = Initial Velocity of Bullet = approx. 2.5*10^8 m/s
vfb = Final Velocity of Bullet = 0 m/s
mb = Mass of Bullet = approx. 5.0 g
vit = Initial Velocity of Thug = 0 m/s
vft = Final Velocity of Thug = ? m/s
mt = Mass of Thug = approx. 80 kg

for the purposes of this problem assume all momentum is conserved in a perfectly elastic collision

If all of the momentum had been conserved (which it hadn't, because if you check the clip, the bullets don't slow down after hitting the thugs, but if it stayed at the same velocity, we wouldn't have any p…

Mission Impossible III

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Mission Impossible III was a pretty standard action movie, and that means that along with all of the climactic fight scenes and the tense shootouts there were quite a bit of questionable physics. I chose three scenes in particular.

The First scene is when Ethan needs to swing from one skyscraper to the next. A few things stand out to me in this scene, the first is that the time the rope catches Ethan he is already at a point that is equal in altitude than his destination, the second is that when the rope catches, Ethan loses a lot of his energy and you can tell because his speed decreases significantly, and the third is that Ethan is producing massive amounts of drag. So, with all of this in place, can he make the jump? First off, lets give some context:

Initial Building: 226 m tallFinal Building: 162 m tallDistance Between: 47.55 m across To make it across such a wide gap would mean that he would need to be going at an incredible speed, but if he is going at such high speeds, there m…