Transformers

Have you ever wondered what those green boxes that say HECO on it are for?  I have seen them everywhere ever since i as a little boy.  Recently i have found out that these boxes are called transformers.  When i first heard this i thought to myself, "Aren't those the robots in the movie with Megan Fox?"  But I soon found out that they were much more than that.  These boxes are called transformers because they actually transform electricity from a high voltage to a lower voltage.  A basic transformer consists of a primary wire and a secondary wire as well as an iron core to connect the two wires.  By changing the voltage of the electricity the electricity can be utilized by household items and will not cause a fire.  Some may think that because you can simply transform the voltage that you can make electricity out of nothing.  This is not true!  The law of the conservation of energy says so. 

To counterbalance the voltage change the current also changes proportioanlly.  So you cannot make something out of nothing.  Transformers can also only transform alternating current.  Without transformers we would not even be able to utilize the electricity we create.  in a more common application transfomers are in every single charger and plug.  So it is very true that physics is all around us.

Current Electricity

As a young boy I asked many questions.  As you know from previous blogs, my father did not know many of the answers to my questions.  So my curiosity often went unsatisfied.  One of the burning questions in my head was "Why do birds not get electrocuted when they stand and the electricity wires?"  Everyday on the car ride home from school i would see numerous birds perched atop the telephone wires.  The question always came to me.  I couldn't understand why the workers that went up there had to wear all kinds of protective gear to work with the wires, but a bird could just go to sit on the wire.  This week in class I finally got my answer.  Mr. Heyler explained to us that the reason that the birds do not get fried on the wires is because there is no voltage difference.  In order for electricity to flow, there needs to be a difference in voltage and also resistance.  But, if a person were to touch the wire while toching another surface that has a different voltage than the wire the would get electrocuted.  I love physics and how it can be used to solve everyday questions like this one. 

Static Electricity

As a small young boy, I loved to play on the playgrounds at the local district parks or at my elementary school.  During recess, I would always be the first one on the playground structure and the last one to leave.  I remember one time where I got into trouble because i stayed on the structure even after recess had ended.  This all changed on one horrible day when the playground fought back.  My favorite part of the playground was always the slide.  I felt like i was going at 100 mph as I glided down the slick and smooth slide.  Sometimes I would go feet first, and other times, head first.  There was even one time where i took of my shoes and stood up as i went down the slide.  But, back to the story, on that horrible day I got shocked by the slide.  I was playing at recess like any other day and after a few rides down the slide I was shocked.  I didn't understand what really happened on that life-changing day until this past week in physics.  Mr. Heyler explained that when 2 objects rub together then they transfer electrons to one another.  This is what happened when i slid down the slide.  When i touched the slide again the electrons flowed back and shocked me.  It is good that i understand this now, but i still don't think i'll be on any slides anytime soon. 

Floating!

This weekend me and my friends decided to go to the beach.  We went to Kahala beach and to our surprise there was a floating island in the water!  We decided to go onto it.  We wondered if it would sink if too many of us were on it, but i thought otherwise because of what i learned in Physics class this week.  i learned that the only way something will sink in the water is if its density is greater than 1000 kg/m cubed.  I figured that there was no way this was possible because the island was filled with air in the middle and air does not have a greater density than water.  My friend who is only in chemistry said otherwise and he wanted to bet me that i was wrong.  i took that bet with confidence because i knew that Mr. Heyler would never lie to me.  when all of us sat on the island it didnt sink so now i am ten dollars richer, all thanks to physics.

changing a tire

this past week when i was driving home from school i experienced a very unpleasant circumstance.  When i was only about five minutes from my home i stumbled upon a very sharp nail which punctured a hole in my front right tire.  i thought to myself, "i dont know how to change a tire...what am i going to do?"  That is when i called my dad.  He was there in no time and he showed me how to change the tire.  he explained first where to retrieve the car jack from and then he went on to explain how to use this strange contraption.  the jack consisted of a lever and the part that lifts up the car.  he went on to lift the jack but the car was very heavy and he was having some difficulty.  This is when i became the teacher, i used the knowledge i had gained during the day of school in physics class to help him.  we had learned that the perpendicular force*radius is equal to the torque so i told him that if he pushed further from the turning point then it would apply more torque and it worked.  i also told him that the same idea applied to the wrench that you use to remove the bolts holding the tire on.  We finished changing the tire in no time and by the end of it me and my dad had both learned something new that day.

tetherball

i remember back in the day when i attended Kahala Elementary school, we used to play tetherball everyday at recess.  i never really understood the whole physics behind tetherball until we learned it this past week in physics class.  all i remember was hitting the ball around the pole really hard.  this past week i learned that the ball swings in a conical pendulum the same way the airplane flew around on the string and how the pig was supposed to fly.  when the object flies in this way it is called a horizontal circle, although the circle is never completely horizontal.  i learned also that there is two types of velocity, linear and angular, both are completely separate and cannot be mistaken for the other.  

Football "punch"

This week in football and in physics i learned how to be a better football player.  Coach Cropsey always tells us to punch our opponents hard so that they will fall down.  All season I've been trying to make my punches harder and this past week i have learned how to in physics.  i took this knowledge with me to the football field at practice and it worked.  At practice my coach was asking me if i have been lifting more, but i just told him that i understand how to punch because of physics.  He asked me what i was talking about so i explained what we learned about impulse and momentum.  I told him that there was no way i could apply more force unless i magically got stronger overnight.  So the way i accomplished this almost impossible feat was by using physics.  we learned that J=Ft=delta p=mvf-mvi.  the part that i used in football was the J=Ft.  By applying the same force over more time i could increase my momentum and also my impulse on the opponent.  This will cause them to experience a greater force and will give me a better chances of winning the "battle" on the field.  My coach was so amazed at this that he applauded me and said "keep up the good work." i was very proud and i look forward to using this new technique out on the field during our upcoming homecoming game.