So my Friend Timmy C. is not the best driver. See he has just stated and doesn't quite get that you cant hit the brakes really hard. So as you can imagine it is a very jerky car ride. And thinking more about this it is because of out mass that we will continue to move forward even though the car has slowed. This is because of inertia and mass is a property of inertia. Inertia is the resistance to acceleration based on mass. So therefore a heavier mass will be harder to accelerate and a lighter mass will be easy to accelerate. Applying this to the car situation above it is easy to understand why we continue to move forward the driver applies the brakes hard because you do not want to decelerate, having mass, so you continue to move forward. Here is an extreme example, caution this clip may be violent in some eyes.
Today in class a cool thought was brought to my attention. The idea that an object that is an infinite distance away from all other objects will have no gravitational potential energy. Its a cool idea because if you think about any object on earth it has its own gravitational field due to the fact that all matter has mass. The earth is a great example of this because we can clearly see the moon and how it travels around the earth which is due to the gravitational pull by the earth on the moon. So thinking of the moon an infinite distance away from the earth than there would be no force acting on it saying that the only planets we are taking into consideration are those in this galaxy. It's weird to think this way with things at an unreachable distance becasue they are not possible and hard to wrap the mind around.
Thinking about what we have been learning in physics, on the topic of energy, it makes it more clear to see some of the physics that goes into taking a shot in hockey. I mean they go so fast but getting there was a little hard for me until this unite that we are in now. Looking at elastic potential energy you can clearly see that in the picture below. It's crazy to see how that potential energy is turned into kinetic energy in fractions of a second and the puck is sent flying at ridiculous speeds.
So this weekend my brother had a hockey game that I went to go watch. I traveled all the way to buffalo to watch his team get beat 5-2. Anyways, during his game he got absolutely destroyed at center ice. It sounds like it would really hurt but getting hit in the center of the ice isn't as bad as it sounds, getting hit against the boards it way worse which I know from experience (I have had my fair share of getting hit myself). But, this got me thinking of why it hurts more getting hit against the boards rather then at center ice. It looks as if it would hurt more getting hit at center ice but it actually doesn't thinking about force over a given period of time. Getting hit center ice means that the force that you get hit with is carried out over a longer period of time rather then against the boards meaning you will feel the force against the boards more because it is carried out over less time. Below are some examples of why it seems lik getting hit open ice would hurt more than at open ice.
A world without friction. That would be something wouldn't it? I cant think of something more hated and loved at the same time more than Friction. I started thinking about this at soccer practice the other day when it was raining out. I kicked a ball on the ground with spin on it but instead of curving it spun going in a straight line sliding a crossed the wet turf. With the coefficient of friction being lower on a wet surface this caused for less friction between the ground and ball causing it to not to curve the way i wanted it to but instead momentum carried it in a straight line. Going back to friction being loved and hated on the topic of a race car, I think this is where it is seen most. Without friction a car wouldn't be able to go forward and thus they need that friction if they want to go anywhere. BUT, then again they are also always fighting against friction trying to get their cars to go even fastest than they already do with things like bearings and probably the biggest air resistance. So thinking about Friction, we only like it was it works for us, not against us.
So last Friday our class of 22 had the pleasure of taking part in a Projectile Lab in which we would shoot our grade. In this lab we would be trying to hit a textbook after making various calculations. Another important aspect of this lab was the fact that if we hit this book the whole class would pass and if we missed the whole class would fail. As many of you know this lab didn't go so hot, crunched for time and lack of communication lead to a complete miss. Mr. Fullerton, being the wonderful man that he is, allowed us to re-due the calculation and write about it in the blog I'm currently writing to receive full credit after that humiliating miss. After doing the calculation again, I came to the conclusion that the book should have been placed at the center of about 2 meters. The thing that messed the class up the most was the fact that there was a lack of time and the push at the end caused for a mix up with numbers due to not being able to think clearly stressed about the time.
After doing this lab and looking back on it, with some more communication it would have helped to make the lab go quicker so we aren't crunched for time also another idea would be to split into into small groups to get an answer which to then compare later instead of trying to work on it as a bigger group. I think that these things are key to this lab to allow for success.
Bellow are my calculations for the value in which the location of the book should have been placed.
I'm really looking forward to this year in physics C. I really enjoyed AP physics last year and it sounds like this year we will be adding onto content that we previously learned which will be great. However, the class so far has seemed pretty terrifying, even though we have only been at it for about 6 days, the thousands of accounts to sign up for and the mountains of work hanging over our heads(which of course has potential to do damage hahaha) makes it look like we are in for a challenging year. But, I do think that with some strict time management and and staying on top of the work it will help to make it easier as we endeavor into the world of physics C.
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