Top Ten Applications of Physics

10.  The number tenth application for physics is using it to find out the gravitational potential energy of an object, using the formula PE=mass times gravity times height.  You can use this to figure out how hard something will hit the ground when dropped from a certain height.
9. The number ninth application for physics in the real world is determining the kinetic energy of an object with the formula KE=1/2mv squared.  You can use this to figure out the force something is going to hit you with, or how much energy an object has while it is moving.
8. The eighth application for physics in real life is determining the rotational velocity of a wheel.
The rotational velocity is how many rotations per second a wheel goes, and this is used for things like figuring out how fast a car is moving.
7.  Number seven is using torque.  Torque is Force times a Lever arm, and it is used to leverage your strength to do things that you normally couldn't, such as turning a really stubborn bolt, or cutting through steel with a really big pair of scissors.
6.  Number six, Gravity.  The way to find out the gravatic attraction is between two objects is:
Gravity= g(m1 times m2)/d^2.  We use this to figure out how much attraction is between satellites and earth, and gravity itself binds the universe together.
5.  Number 5 is centripetal force.  Centripetal force is the thing that causes you to be forced up against the side of a car that is spinning in circles.  You use it every time you wash your clothes, because the spinning motion of the washing machine causes the water to force itself out of the turbine, letting your clothes get spun dry(er).
4.  Electricity!  Without electricity we would not have any of our wonderful technology that we use today.  Electricity is a current, and current is voltage/resistance, which is shown by Ohm's law.
3. Circuits are methods of moving electricity from one place to another.  They have to be a completed loop, and you can turn the flow of electricity on and off by breaking the circuit.
2. Magnetism.  Magnetism is a product of aligned domains in ferromagnetic materials.  Domains get aligned when either subjected to an aligned magnetic field, or getting hit with something while exposed to a very weak magnetic field (such as the Earth's field).
1.  Number one is generators.  Generators are ways of producing electricity by moving a magnet across coils of conductive wire.  You input force, and out comes electricity.  This is the best way to produce electricity.

Wind Turbine Blog

Me and Manuel constructed our wind turbine using several pieces of PVC pipe, and well as a plastic dustpan and the magnets and copper wire that were used to make the generator.  What we did was that we used the PVC pipe to make the housing of the wind turbine, and cut the dustpan into a pinwheel design, in order to catch the wind more effectively.  Inside the housing, we attached four coils of wire on the interior of the pipe, and to the turbine shaft we attacked four magnets.  As the turbine spun, the magnets would spin over the coils, generating electricity.

Blog Reflection 5-12

In this unit we studied electricity and magnetism, as well as practical applications of each.  We learned about the directions of magnetic fields, and about how the field flows from the north pole of the magnet to the south pole of the magnet, and about why the like poles repel each other, while opposite poles are attracted to each other.  We also built an electric motor, made out of a magnet, a battery, a coil of copper wire and a paperclip.  A motor is like the reverse of a generator, in that a motor takes electrical power and generates force, while a generator takes force and uses it to move a turbine to generate electrical power.  Certain electric cars can convert their motors to generators when they are coasting.  We also learned about transformers, and about how they only work with alternating current and not direct current.  The equation to find the change in voltage from primary to secondary, (input to output) is Vp/Tp = Vs/Ts where V is voltage and T is turns.  we also learned about how magnets generate a magnetic field due to the fact that they have aligned domains, which are groups of electrons and that any ferrous metal exposed to a magnetic field will start to generate an identical magnetic field of it's own.  This includes nails exposed to the earths magnetic field and hit with a hammer.
        I had no particular difficulties with this chapter, but once again, the formulas were troublesome.

Unit Blog Reflection

This unit we learned about electric currents and electric fields, including Ohm's law and Coulomb's law, which are I=V/R, and F= ke q1q2/r^2.  We also learned about electric fields, and what the diagrams portraying electric fields actually mean, which is that the arrows in the diagram  are the direction that a positively charged particle will go when placed into that electric field.  Besides that, we also learned about the different kinds of ways that an object can gain a static charge, which are through either friction, induction or .  Friction occurs when rubbing two objects together, induction occurs through polarizing an object and then drawing off the positive charges with another object, and .  After that we learned about electric currents, and that the electric charge in a current doesn't really flow through the wire (or whatever object is carrying the current), it needs to fill the entire thing at once, or else it can't flow at all.

This is an example of a simple electric circuit.  The battery is the source of the electric field, the switch exists to break the current and the lightbulb is the thing being powered by the current.

The different kinds of electrical circuits are called series circuits and parallel circuits.  Series circuits have everything on one wire, while parallel circuits have multiple wires independent of each other connected to the same source.  If one segment of line goes down in a series circuit, it shuts off the whole thing but for a parallel circuit any of them can be broken and not affect the others.

       This unit may be the one that effects our real lives the most, because everyone uses electricity.  It's good to understand how it actually works.  The things I had trouble with were mostly remembering the formula's, and in truth I still haven't quite got them down.  However, when I do it will mostly be through repetition.

Current Resource

This is a video from Khan Academy talking about circuits.  It is part of a series of 4 videos, but in this one he talks about current, resistance, and voltage.

Voltage Resource

This is a video of some maintenance workers playing with a power line.  In it, you can see how they are using heavily insulated suits, and still have electricity arcing from the power line to their hands.  You can hear the electricity moving through the air and it gives a very visual representation of an example of high amounts of current.

Mousetrap car

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Mine and Manuel's car traveled exactly five meters in just over nine seconds.  It involves Newton's First and Second laws, using the inertia of the mousetrap to keep it in place as it spins the axle, as Newton's first law states that an object at rest will stay at rest unless acted on by an outside force, and an object in motion will stay in motion unless acted on by an outside force.  We attached a 100 gram weight to the mousetrap to increase it's mass which also increases the force required to make it move.  When it can move the axle without being moved itself, the car moves.  We didn't increase the lever arm of the mousetrap, which may have contributed to it only going five meters.  Our mousetrap car moved very slowly, because it had a lot of mass, therefore the comparatively small force of the mousetrap closing was not enough to make it move quickly.  We used two frisbees, a pencil, a piece of wood and the mousetrap to make our car.  The mass may also have contributed to how quickly it stopped once the lever arm stopped moving it.

Reflection:  Our mousetrap car was very makeshift.  We are lucky it worked at all.   If we could do it again I would spend more time gathering materials, and also make sure that we had our mousetrap before the say of the final run.  Just in general, more effort all around would be nice.