Sunday, September 27, 2015

The Laws of Gravity and Superman

The chapter I summarized was about newtons law of gravity and its affect on Superman. I thought that this was appropriate because this is what we are focusing on in class. The chapter starts by asking the question how can Superman just leap to the top of a building. Then comes in the physics. It takes into account Superman's mass, the distance he is from the Earth, and the universal pull of gravity. It concludes to say that while on earth his weight not his mass is about 220 pounds. They do this by taking his mass and multiplying it by Earth's gravitational pull. They discover that the acceleration due to gravity which is the equation (G x Mass of the Earth)/ Radius of the earth squared. They discover that his gravitation acceleration is 32 feet/ sec squared. They discover that in order for superman to make that leap he would have to be from a planet with 15 times the gravitational pull of Earth. It goes on to explain why the Moon revolves around the Earth and the Earth around the Sun. It explains this by saying, the Moon is falling around the Earth and that the Earths gravitational pull determined by the size of the Earth keeps the Moon in close. But the speed that the Moon is falling at keeps it from striking the Earth. It also goes on to say that the shape of the planet is determined by its size. If the planet or object is larger than about 300 miles then is gravitational pull forms it into a sphere. Also a shout out to the movie Armageddon, if the asteroid was as big as they say it was then it would be in the shape of a sphere not the shape showed in the movie. They continue to break down the reason that Krypton's gravitational acceleration is 15 times stronger than Earths. In order for this to be true, Krypton must be 15 times larger than Earth or the same size as earth but 15 times denser. Due to the laws of gravity for earth that they would assume were true on krypton, it would be impossible for Krypton to be 15 times dense as earth. They explain this by saying that the density is equivalent to how close the atoms are packed together. The closeness that the atoms would have to achieve to produce a density of 15 times the Earths is nearly impossible due to quantum mechanics. But if it were possible some how it still geology wise be near impossible. The Earth is the most dense planet in the universe at 5 grams/ cubic cm. So even if the planet was made of uranium it would only have a density of about 19 grams/cubic  cm. Which is less than four times the density of Earth. So to acquire 15 times the density of earth it would have to have the density of 75 grams/cubic cm. There is no natural substance that has that kind of density. But in defense there have been exotic materials found in outer space, although none to my knowledge are dense enough there still is a possibility. They go on to say that it is just as unlikely that the planet could be 15 times larger than Earth. Jupiter which is 11 times the size of the Earth, which is pretty close to our magic number of 15 times the size of Earth. The problem is that it is so large that the atoms are all spread out and that it's really just a big ball of gas. Making it impossible to even walk on much less build an entire civilization on.  But there is one exception, If the core of Krypton comprised of neutron star material which is the material of a star after it has exploded, with a radius of about 600 meters. It would have the density that of 15 times that of Earth. But with this the planet because of its extreme density would not be able to distribute mater. There would be volcanic eruptions and large tectonic shifts. This would essentially  cause the planet to fall apart. Also this would persuade mothers to put their infant in a rocket and send him to a far away planet called Earth. Where the child would discover his abilities and save the world day after day from evil villains.










Thursday, September 17, 2015

Armageddon

After watching the movie in class and crunching the numbers, the plan in the movie Armageddon was complete junk. With this said though it is not unreasonable to say that NASA has not thought of coming up with a plan to attack these Armageddon Asteroids. NASA is planning on bringing an asteroid into the moons orbit allowing astronauts to land on it and conduct experiments and collect information. But in order for this plan to work they will actually have to retrieve an asteroid from deep space. That would be the first manned mission into deep space. These plans are all still in the works. As it stands now NASA just tracks and identifies asteroids. But even if this mission was to take place and was successful it would just be the first step. After studying the asteroid they would then have to come up with a strategy on how to destroy one. The plans though for this mission to actually happen is still years in the making.

Another idea people are developing is the use of nuclear bombs. They are trying to discover the amount of kick a nuclear bomb would have on an asteroid in outer space. They do not want to blow the asteroid up but change its direction. They do not want to explode the nuke on or under the surface but close to it to create a kind of push against the asteroid. They also need to detonate it far enough in to outer space so it's radiation doesn't affect earth. It is difficult to do this experiment on earth. They have discovered how much kick they have on earth but space is another thing. I am sure it won't be too long to figure out how to conduct this experiment in outer space.

Friday, September 11, 2015

Erased

In the movie Eraser, Arnold Schwarzenegger's character mans himself with two rail guns and kills the villains. I will be breaking down the bad physics of this scene. This problem will take into consideration the mass of Arnold, the villains, and the bullet. It will also take into consideration the velocity of Arnold, the villains, and the bullet before and after the shot has taken place.

This scene is a law of conservation of momentum problem.

momentum= (mass)(velocity)

P= momentum
Delta= change in momentum
f= final momentum
i= initial momentum
M= mass
V= velocity
a= Arnold
b=bullet
v= villan
kg= kilograms
m/s= meters per second

Delta(P)=(Pf)-(Pi)=0

Arnold firing the gun

(Ma)(Via)+(Mb)(Vib)=(Ma)(Vfa)+(Mb)(Vfb)

(100kg)(0)+(.1kg)(0)=(100kg)(-30,000m/s)+(.1kg)(30,000,000m/s)

0= 2,970,100

As you can see this does not make sense so this part of the movie is impossible.


The bullet hitting the villain

(Mv)(Viv)+(Mb)(Vib)=(Mv)(Vfv)+(Mb)(Vfb)

(80kg)(0)+(.1)(30,000,000m/s)=(80kg)(37,000m/s)(.1kg)(30,000,000)

3,000,000=5,960,000

As you can see this does not make sense either.

From a physics stand point this whole scene does not make sense at all.













Wednesday, September 2, 2015

Mission Imposible III

In the movie Mission Impossible III Tom Cruise's character is trying to retrieve some kind of terrorist device called the Rabbits Foot. He comes up with the idea of swinging from the roof of one building to another. The question is, is it possible for him to successfully make the swing? The distance between the two buildings is 47.55 meters apart. The hight of the tallest building is 226 meters. The hight of the lower building is 162 meters. The time of the swing was about 15 seconds. Is it physically possible I don't know.

The second scene from the movie that I am investigating is when he jumps from the building. The question is, is it possible for even at the maximum altitude of the building to make a successful jump. The minimum height that you can jump from and survive is 100 feet. Without some kind of injury you need a jump of at least 300 feet. The building is 162 meters tall. So at the top of the building it is possible to make a safe landing. He was at about half way up the building when he jumped.  So he jumped at an altitude of about 81 meters. That is roughly 243 feet. He should have not been able to walk away from that without at least a limp or some kind of mild injury.

The last scene is when Tom Crusie's character has to make an incredible bridge jump. The bridge gap is about 25 feet. The length of time he was in the air can not be calculated because he's in slow motion. His weight is about 170 pounds. The speed at which he is running is unknown. The force pulling him down is 9.81m/s squared. He jumped from a level plane. Whether its is possible or not is unknown to me but it is very unlikely.