Physics Unit 5 (Part 2)

In class today, we learned about Newton's last two laws of physics, so I thought that I would spend this whole post just going over what each law means and how it applies to every day life.


The first law is the Law of Inertia, which states that an object in motion tends to stay in motion while an object at rest tends to stay in rest unless an outside, unbalanced force acts upon it.

The picture above shows Caitlin and me in Driver's Ed, which is a three hour class we attend on Mondays and Wednesdays after physics, and as you can see, we are enjoying every minute of it.  In terms of Newton's first law, Caitlin and I are the objects at rest. We basically sit in the exact same spot hours at a time doing pretty much nothing. In Driver's Ed you eventually give up staring at the clock and sink deeper and deeper into a haze of tiredness and road signs. By the time you are two hours into Driver's Ed, all you can do is fight to stay conscious, so when the instructor announces that it's time to go on break, you are so unprepared for the news that you are instantly overwhelmed with the feeling of elation. Said elation, in relation (it rhymes!!) to the Law of Inertia, is the unbalanced force that pushes the object at rest into motion, and is what causes Caitlin and me to move out of our states of rest and practically skip out of the classroom to do a celebratory dance. 

Newton's second law is the Law of Acceleration, which states that the acceleration of an object is directly proportional to an object's net force, and the acceleration of an object is also inversely proportional to the object's net mass. The equation for the law is Acceleration = Sum of force ÷ mass. 

In this picture we see our friend, Bob, who likes golf. Newton's second law talks about how acceleration is equal to the amount of force of an object divided by its mass. Bob just hit a golf ball, and it has a high acceleration.

Now, in this picture we see Bob, trying to hit a truck out of the way because it is right above his golf ball. Unfortunately, our friend Bob isn't all that smart, and he thinks that he would be able to move the truck if he hits it with his golf club. Bob had swung with all his strength when hitting the golf ball, and since it went so far, he thinks that if he hits it just as hard, the truck will move. Too bad Bob didn't know about Newton's second law of physics. Because the mass of the truck is so much greater than the mass of the golf ball, the acceleration of the truck is going to be a lot less than the golf ball's. In other words, the truck isn't going to move at all.



Newton's last law of physics is the Action-Reaction law, which states that for every force (action), there is an equal and opposite force (reaction), which is equal in magnitude, but opposite in direction.

In this picture, my friend's and I are playing a game at Dave and Buster's that involves pushing the buttons that light up in order to get more points. My friends and I are very aggressive, so we ended up hitting the buttons incredibly hard, which in turn, made our hands incredibly sore after. Part of the reason why our hands were so sore, besides the fact that we were just slapping hard plastic over and over again, is because of what Newton's law stated. As we were hitting the buttons, the buttons were pushing back against our hands with the same amount of force that we were hitting them with. In other words, the whole time we were slapping the buttons with all our strength, the buttons were punching us back just as hard. It's funny, because right now the "I am rubber, you are glue; whatever you say bounces off me and sticks onto you" saying is going through my head right now, and it actually applies to Newton's law in a way, except instead of saying something we're just hitting the rubber and the rubber's just hitting us right back.