Warmer Waters: Good for Bathing, Not for Fish

Recently I was watching a very interesting nature documentary on Netflix called Our Planet which shows absolutely stunning footage of natures true beauty while a narrator informs the audience about the life that is being shown. If you have not seen it I highly recommend it. Anyway, as I was watching the show one major theme seems to pop up all the time and that is global warming/ climate change. This seems to be man's largest global crisis right now and it is greatly affecting our planet. In this blog I would like to inform everyone about a part of climate change that many people know or talk about and that is our oceans. Along with many places around the Earth, our ocean's are becoming warmer. This is affecting the life that live in those waters more than most know.

One of the biggest problems facing our ocean's ecosystems is coral bleaching. While only taking up 1% of the sea floor, about 25% of marine species live in coral reefs. Healthy and productive coral reefs are on of the most important ecosystems on the planet. When the ocean's temperatures get too warm, the coral start to get rid of the plants that live within them that help them get food and in turn, they turn white. This is referred to as coral bleaching. Over 1000 km of Great Barrier reef bleached in 2017 and many of those coral died like in the image above. Without coral reefs many of our ocean's species will die.

If you want to see more about the state of our coral reefs and all of our planet's ecosystems go to ourplanet.com. Our Planet is not only a documentary on Netflix informing us of the effects of global warming on Earth but is also an organization run by the World Wildlife Fund (WWF) to try and educate the world on how we can fix global warming.

What is Weightlessness?

The word weightlessness is a very misleading term because, as the name sounds like it implies, it should mean that a person is weightless as in they do not have weight. However, this is not the case. It is a very common misconception that weightlessness means you do not have weight but in reality you are just in perpetual free fall.

Weight is defined in physics as the force acting upon an object due to its mass. Or in simpler terms, weight is a force that is equal to an objects mass times the acceleration due to gravity, F=mg. Weightlessness is not an absence of that force, in fact it is the complete opposite. Weightlessness is when the only force acting upon an object is the force of gravity or its weight.

The force that we perceived as our weight is actually the normal force of the floor pushing against our feet counteracting your weight. When you feel weightless it is actually because of a canceling out of a normal force so it is essentially not acting. This is achieved by having a centripetal force act in the opposite direction of the normal force.

When in orbit, which is an example of being weightless, the force of gravity is always directed toward the Earth, the normal force is always opposite and the gravitational force. Then  the centripetal force is always directed toward the center of the circle as represented in the image below.

So when an object is weightless it is the centripetal force cancels out the normal force and the only force acting on you is the gravitational force. 

Newton's Law's in Motion

Avengers: Infinity War is a fun and exciting action movie that takes place in a universe with many super powered heroes and villains fighting it out in battles of phenomenal scale. What the lack in realistic physics and proper application of physical laws, they make up for with cool visuals and ridiculous feats. I would give Infinity War a NR for its obvious ties to comic book physics and ignorance of actual physics. 

Newton's 1st Law

Sir Isaac Newton's first law of motion states that an object in motion will continue in that motion forever until acted upon by an outside force. A perfect example of this principle being ignored in Infinity War comes right at the beginning of the film. When Thanos destroys the ship with all the Asgardians on board there is quite a large explosion. With an explosion of that magnitude debris (like Thor who was inside the ship when it exploded) would be hurled away from the spot of the explosion at a non zero velocity. When the Guardians find Thor though, he is just floating around where the ship was with no real noticeable velocity. By looking at the motion of objects in the background and comparing it to Thor it seems that the perceived motion of Thor is coming from the motion of the Guardian's ship, and not from Thor. In reality, the debris that was flung into space, like Thor, should be a ways away from the spot of the explosion because it would not have any outside forces stopping its motion so it should travel in a straight line away from the wreck at the speed the explosion set it at. 

Newton's 2nd Law 

Newton's second law of motion states that if there is an acceleration of on object with mass, then there must be a force applied to it to cause the acceleration. The biggest disregard for this law in the film is how Ebony Maw and Doctor Strange just levitate in the air without any sort of thrust upward. For them to float they would need to supply a force greater than and in the opposite direction to their gravitation force to lift themselves off the ground and then a force equal to their weight while in the air. Neither of these magicians supply any sort of visible force to allow them to float in mid-air but the movie just looks past that and allows them to do it anyway.

Newton's 3rd Law

Newton's third law of motion states that every force exerts a force with equal magnitude but in the opposite direction to the original force. One moment where this seemed to be ignored in Infinity War is when Thanos pulls one of Titan's moons and throws it at Iron Man. While the movie shows Thanos pulling and exerting a force to pull the moon downward, there is not indication of Thanos having an equal and opposite force acting against him. If there was an equal and opposite force, he would either be flung from the surface of Titan or if he was anchored enough, Titan would shift toward the moon.