Friday, January 18, 2019

Force | Pushes and Pulls

Forces and Motion: Basics by Phet
Have you ever seen a Star Wars movie or heard people saying “they have the force”? The Star Wars franchise is famous for its use of the “force”, otherwise known as Jedi’s power to move things without touching them. But out of Star Wars, what is a force? It’s pretty simple, a force is a push or a pull. Really? That’s it? Well yes, and no. Forces may be as simple as a push and a pull, but Isaac Newton describes them as more. Newton has three famous laws that are used to determine forces. Number one, an object at rest stays at rest and an object in motion stays in motion unless acted upon by an unbalanced force. But what does this look like. Take your pencil. Say you dropped your pencil off of the table. Your pencil stays in motion until it hits the floor and stops. You could argue that the floor is not a force, but is it? Right now, as you are standing, their are at least two forces acting upon you. Force number one, gravity. Gravity is currently pulling you down towards the earth’s center. This is what keeps you from floating around. Number two, the push of the floor. The floor is actually pushing you upwards. If it wasn’t, you would currently be sinking down into Earth’s core. This brings us back to your pencil, and Newton’s second law. This law states that F=MxA. Or Force equals Mass times Acceleration. Say that you pencil was the size of the desk you are dropping it off of. This would take a lot more push from the ground, or force, to keep this giant pencil from sinking into Earth’s surface. Which brings us to Newton’s third law. For every action, their is an equal and opposite reaction. Back to your pencil, when you drop your pencil it bounces back up a little bit. This is because of Newton’s third law. The action is your pencil dropping, the reaction is it coming back up and off of the ground in the opposite direction that you dropped it. There’s more to forces than Newton’s three laws.

Their is also a such thing as net forces. Net forces are the sum of all forces acting upon each axis. Things brings us back to you and the battle between the ground and gravity. The fact that you are not sinking into the ground, but not floating off to space is because the force of gravity and the force of the ground have a net force of 0. This is because each force is acting upon you with the same strength. The strength of a force is measured in Newtons or N. Back to your pencil, this time, your are sliding your pencil across the table to your friends. If you picture your pencil on a coordinate grid, it might help you. There are about 4 forces acting upon your pencil. Force one, gravity. For this problem, we will say that gravity has a strength of 150 N. Force two, the push of the table. We will say that it also has a strength of 150 N. Since these two forces are equal in strength and going in the opposite direction, they cancel each other out. This means that your pencil is neither moving up nor down. Force three, friction. The friction of the table is pulling your pencil back towards you, or in the opposite direction that the pencil is moving. We will say that it has a magnitude of 10 N left. Magnitude is the strength of the force as well as the direction. Force four, your push. Your push has a magnitude of 50 N right. Now to calculate the net force. The net force of the y-axis (as we figured out earlier) is 0. Now the net force on the x-axis. Since the two forces on the x-axis are going in opposite directions, we can assign the one going left the negative number. This would make the equation 50 N - 10 N. Then just subtract. The answer would be 40 N right, because that is the way that the pencil is moving. There is a lot to forces, but once you get the hang of it, it is pretty simple. A force is a push or a pull.

S&EP
SP8: Arguing from Evidence

Imagine this, hulk and the avengers are having a tug-o-war. Who do you think would win? I don’t have to imagine this. I argue from evidence when I said that the avengers would win because they are actually applying force, and a lot of it. Whereas, the Hulk is just standing there reading a book. Therefore, the avengers would win because they are actually trying. But not only do forces backup tug-o-wars, they also disprove double-jumping. Double-jumping, as I argued, is not possible. To leave the ground, you need the spring effect of you feet pushing down on the ground and the ground pushing up on you. As you probably know, the air does not push up on you, so for you to jump you would need some kind of solid force underneath you. Therefore, you can’t double-jump.

XCC
XCC: Stability and Change

Forces both stabilize thing and change them. When forces are balanced, they can stabilize things and hold them in place. Just like how the push of the earth and the pull of gravity keep you stable and on Earth’s surface. Or when the push of the table and the pull of gravity kept your pencil still on the table. But forces can also change things. Unbalanced forces cause things to change, especially in position and placing. Unbalanced forces is what causes objects to move and change their position. Like when you are rolling a ball, the ball was unmoving, balanced and stable, but your pushing was an unbalanced force that caused the ball to move, changing it’s position to another place. Forces are part of nature and are everywhere, you don’t have to look for when you want to see it.

Tuesday, January 8, 2019

Driverless Cars | Are They Worth The Risk?

jpartsch0506
Mrs. Garcia
Science 8
Jan 8, 2019


      Technology is everywhere. We see it in our daily lives as we stare at our phone screens, work on our computers and we will even start to see it whenever we get on the highway. Driverless cars, driverless cars are about to become the next big thing in technology. These autonomous vehicles are a topic of debate amongst scientists, some say that it can help to reduce traffic and accidents, but others disagree, arguing that the technology just can’t do what a human can on the road. Though the thought of not having to be behind the wheel is tempting, the risks outweigh the good, and scientists aren’t even at the point where they can guarantee that there will be less accidents and traffic. Not even counting that the vehicles can’t function properly in situations like heavy rain, snow and other bad weather. All of this adds up to the big question; Are they worth the Risk?

      Driverless cars just aren’t worth the risk. Millions of people die each year from car crashes, but scientists can’t even guarantee that these cars will fix that problem. Driverless cars can’t work as well in bad weather and are more prone to hitting pedestrians. In the Tech and Innovation Channel Video, The Pros and Cons of Autonomous Vehicles, their guest, Dr. Billy Abraham, states, “...another concern is that if there are not enough autonomous vehicles on the road we'll have accidents because if you don't have 100% autonomous vehicles it means that you know regular cars will bump into you etc….” If there is not almost 100% of autonomous vehicles on the road, the ‘accident free’ side of the argument doesn’t really work because it needs and all or nothing scenario to fully prove it. Also in the Junior Scholastic article Are Driverless Cars a Good Idea?, Section NO by Jamie Lincoln Kitman, it states, “Although Google’s cars have not yet officially had an accident where they are at fault, critics are still concerned about how computer error may endanger lives on the road, particularly at high speeds…” Also in the NewsHour Extra article Are We Ready for Driverless Cars, by Ibrahim Balkhy, it states, “Take, for example, the idea that self-driving cars will lead to tens of thousands fewer highway deaths each year. The truth is, no one knows for sure how many lives could be saved by driverless cars. That’s because data on the role of human error in crashes relies heavily on self-reporting and is therefore incomplete. If many driverless cars are operating in close proximity at high speed, some accidents are likely to involve more vehicles and be even more deadly than the accidents we know today.” Scientists can’t prove that it will help cause less deadly and just less in general, crashes. There are a lot of things that these cars can do, but the promise of no accidents is just not realistic.

      Furthermore, driverless cars are not very good when working in bad weather or harsh conditions. In areas that get heavy rain, bad storms, and snow, driverless cars aren’t the best options. The weather causes disturbances with the cars sensors, thus making it so that they can’t drive safely. In the NewsHour Extra article Are We Ready for Driverless Cars, by Ibrahim Balkhy, it states, “Opponents also question whether driverless cars will be able to operate in bad weather, since heavy rain or snow could interfere with the vehicles’ sensors.” Furthermore, in the Junior Scholastic article Are Driverless Cars a Good Idea?, Section NO by Jamie Lincoln Kitman, “Currently, the car’s sensors are unable to cope with poor weather conditions like heavy rain and snow-covered streets.” Thus, driverless cars don’t work that well in areas that have bad and/or harsh weather. The cars sensors are messed with and can make for bad driving and more accidents.

      Driverless cars will also put people out of their jobs. Since people will have driverless cars that they can summon, there is no more real need for taxi drivers, truck drivers, Uber drivers and other people who make money off of transportation. All that you'll need to do is go into your app and call a driverless car. Thus, many people who used to be those drivers will now be without that job. In the Tech and Innovation Channel Video, The Pros and Cons of Autonomous Vehicles, their guest, Dr. Billy Abraham, states, “...disadvantages of the autonomous vehicles is the fact that a lot of people are going to lose their jobs according to certain estimates about 4 million people are going to lose their their jobs... 29 states in the United States the most popular or the most common job is a driving job so they're going to lose their job so we're talking about taxi drivers we're talking about pilots ok that means for uber and all those apps lose their job  …” Many people drive and do transportation for a living. Once we make driverless cars a things, they won't really be needed to do that any more.

      Another concern is that they won't actually prevent that much traffic. In fact, scientists have found that it will actually create more traffic. This is because humans have the ability to adapt and be creative. If they are stuck at a light, they might cut through a parking lot. They might take a backroad if the interstate is crowded. Scott Le Vine, Alireza Zolfagharib, and John Polak are researchers from the Department of Geography at SUNY in New Paltz, New York, their work plus other studies disproves the theory that driverless cars will make traffic better. The News Atlas article, The Pros and Cons of a Driverless Future, by Tony Borroz, he states, “In every single test, self-driving cars were calculated to create a comfortable, rail-like ride made congestion worse than it would have been in a baseline scenario with people behind every wheel...Going for high-speed rail style of smoothness, those numbers got even worse: Delays increased from 36 percent to nearly 2,000 percent and intersection capacity fell between 18 percent and 53 percent.” It turns out that driverless cars actually caused more congestion and made it so that their was more traffic on the main roads and highways.

      Their is also a concern when it comes to hacking. Now days, hacking is becoming a bigger and bigger problem. It has been brought up at a political level and is a major problem. Now that our cars will be hooked up to some kind of internet, their is the possibility that they can be hacked, this would then make for a big problem with driverless cars. You wouldn't want someone who has an intention, that is most likely other than your own, having control of the vehicle that you are in. People could use this the wrong way and cause big accidents and issues. In the Tech and Innovation Channel Video, The Pros and Cons of Autonomous Vehicles, their guest, Dr. Billy Abraham, states, "...one of the concerns is that people will be able to hack and even route your  car to a different direction [from] where you want to go..." This means that people could control your car and use it to do stuff for them. This would mean that your life is potentially in their hands. Many people would agree that they wouldn't want someone else controlling where they are going and altering what they were supposed to be doing while in their car. This brings me to legal issues, along with the issue of hacking, another is insurance. If two driverless cars crashed into each other. Who would be responsible? Who's insurance would pay? In the PBS NewsHour's article, Are we ready for Driverless Cars? by Ibrahim Balkhy, he states, "...The question of legal responsibility also remains a sticky issue. If one of these vehicles collides with another, or with a human-driven car, whose insurance pays the claim? If a police officer pulls over a driverless car, who gets the ticket?..." Hacking could also cause accidents, which could make legal issues, this could become a big issue in the future of driverless cars.

      Many people argue that they would rather have driverless cars on the road than 16 year olds and 80 year olds. Many people would agree with this statement. They say that they would feel more safe and comfortable in a driverless car than behind an older person or new driver. They believe that they might reduce the number of accidents because people wouldn’t have older or young drivers on the road that can’t drive that well. In the Wired article, Puny Humans Still See The World Better Than Self-Driving Cars by Aarian Marshall, the author states,‘"You’re probably safer in a self-driving car than with a 16-year-old, or a 90-year-old,...”’ Nonetheless, many people also say that the majority of people would rather have middle aged people on the road that are responsible, rather than driverless cars. They say that middle aged people are more reliable than the driverless car. Plus, middle aged people make up the majority of people whom are driving on the road. In the Wired article, Puny Humans Still See The World Better Than Self-Driving Cars by Aarian Marshall, the author states,  “...says Schoettle. ‘But you’re probably significantly safer with an alert, experienced, middle-aged driver than in a self-driving car.”’ Driverless cars may be a good replacement for people who aren’t as good as driving, but not for those who are.

      Furthermore, driving involves a lot of sensing, hand signals and sight. Drivers can communicate to each other, pedestrians and bikes. There are also pot holes, stop signs, and faded lines that indicate the lane that you are in. Scientists are concerned that the driverless cars won't be able to sense these thing and communicate how drivers would on the road. “Still, many aspects of driving depend on small gestures and signals. Would a driverless car know to stop or slow down for a construction project? Other situations like giving the right of way or waiting one’s turn at a stop sign appear to be issues of judgment that would be hard to perform without a human brain.” states Ibrahim Balkhy in his article Are we ready for Driverless Cars? Additionally, in the article Are Driverless Cars a Good Idea by Junior Scholastic, the author states, “Then there’s infrastructure to consider. Many driverless cars require smooth roads, with clearly painted lines, to safely position themselves. Potholes and other irregularities could become even greater hazards. Our infrastructure is already underfunded. Where will the resources come from to maintain and repair roads and bridges to this new, higher standard?” It is hard for these driverless cars to sense all of this stuff. It would be unreasonable to keep all of the roads neat and cared for, it would also cost a lot of money and time. Thus, driverless cars would not be as good on the road as human drivers.

      Driverless cars do have their upsides, but the downsides are clear. Driverless cars are hackable, puts many people out of their jobs, doesn't really prevent accidents and could cause more fatal ones, causes more traffic and makes for more time on the road, don't work well in harsh or bad weather, can't communicate and be as aware as human drivers, and cause many questions when it comes to legal responsibility. Driverless cars just aren't as good as an alert, middle aged, well taught human adult. Instead of spending so much time on crafting driverless cars, they should spend more time properly teaching people to drive and drive responsibly and safely. The bad parts of driverless cars outweigh the good. So the next time that you pick up your car keys and get behind the wheel, just be glad that the wheel is still there.

Is there life in Space?

News | The Solar System and Beyond  by JPL - NASA Have you ever watched sci-fi movies where there are aliens or extraterrestrial life, ...