Before I started this class, I figured that my morning routine was simple. However, after nine months of physics, it is not as simple as I once thought. The static shock from my car in the winter was habitual, and the coffee cup falling off of it was old news. However, physics has changed my perspective on my morning. Let me set the scene...
One morning, I miraculously woke up early on my own and thought it would be fun to curl my hair. As I went to plug the iron into the outlet, I remembered that it was safe to stick something into one socket, but not both at the same time because that would complete a circuit and cause a charge. I carefully plugged the appliance in, and my hair looked great.
Next, I went to start the car, but since it had just snowed, it had trouble starting. Luckily I knew that since it was cold, the wires in the car were less likely to carry current, and this was why no energy was getting to the engine. I tried starting it a few more times before it turned on, and then I proceeded to turn on the heat full blast.
As I was driving through my neighborhood, I thought about how the wheels in my car propel me forward. The outer rims of tires are longer, but complete fewer revolutions. The inner part of the tire is shorter in length, and therefore must complete more revolutions to keep up with the outer part. The outer part has a higher rotational inertia because it is harder to rotate. Likewise, the inside part has a lower rotational inertia because it can make revolutions easier.
Having completed the motor lab, it was a realization to me that in a nutshell, my car operates on a magnet and a current carrying wire. Although it is a bit more complicated, I think that its wild that a motor consisting of two materials can create something as complex as a car.
Now driving down the hill to Starbucks, I see that the light at the bottom of the hill changes to red. I'd better slow down if I don't want to crash! I put my foot on the brakes and remember that the force of friction is equal to the net force of the car. If my car weighed 2000N, then the ground is pushing back on the car with 2000N of force in order to make it stop.
Once I safely get to Starbucks and order my coffee, I set it on top of the car while I put my bag in the back seat. I sit in the driver's seat ready to go when a stranger yells, "Hey you, your coffee's on the car! It will fly off when you start driving!" Jokes on them, because I know that according to Newton's First Law, objects in motion or at rest will stay as such unless acted on by an outside force. Because the cup is at rest on the top of my car, it will fall directly below where it was sitting if I moved quickly.
Now in the car with my coffee, I remember to put on my seatbelt! They are extremely important because as Newton's First Law states, all objects in motion or at rest will stay as such unless acted on by an outside force. If I was riding in a car and got in a crash, my body would continue to move forward because I am inside the car. Luckily, seat belts act as an outside force that stops me from going through the windshield.
As I merge onto I-240, I realize that there isn't another car on the road which means that I can safely drive on cruise control for a few minutes. Just like the coffee cup at rest is at equilibrium, so is my car when at cruise control. There is no net force acting on the car, and it can go at the same speed forever without stopping (if gas didn't exist).
Finally I arrive at school, but no matter which way you drive onto campus, there is a steep hill that you have to drive up. Going up a hill is work because there is a vertical distance and a force. You cannot directly increase or decrease work, but you can change the distance or force by using simple machines such as pulleys and ramps.
I pull up to the day hall and sip some coffee. I get out of the car, and when I go to close the door behind me, I remember what we learned about force and lever arms the day before. Force and Lever Arm are inversely proportional, so if I tried to close the door close to the hinge, it would be difficult because the force is strong and the lever arm is short. This is why it is much easier to close doors by the handle so that there is less force.
Who knew that all of these things and more would be present during one 30 minute journey to school! Physics is everywhere- you can run but you can't hide! Actually, running involves physics because of action-reaction pairs, but oh well.
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