Thursday, May 1, 2014

Refraction

In the water, spoon appears to be disproportionate to the top half. This is an example of refraction. This happens because the light bends at the second medium. As the light passes from air to water, one part of the wave slows down due to contact with the medium, while the other part not passing through the medium is moving faster. The light bends until both parts have passed of light ray from air to water.

Monday, April 7, 2014

Convex & Concave Mirrors at Home

A convex mirror bulges outward to reflect a wider angle at edges, and the image is smaller than the actual size. Smaller images for the car side view mirrors allows you to see more of the road. The law of reflection means that when Light hits a surface, it bounces off in a particular way. This is a virtual image since we think the light is coming off the mirror in a straight line. 



Concave mirrors bend inward in order to make objects larger. Concave mirrors can produce a real image due to the way their curve bounces light. Due to a focal point, the object seems upside down from far away but not up close. 

Wednesday, March 19, 2014

Generators

A generator is a device that moves a magnet near a wire to create a flow of electrons. The he action that does this varies, but the general idea is the same. 

Windmill
The turbine blades capture the kinetic energy in the wind. When the blades start to move, they turn a shaft that leads from the rotor to a generator. In the generator, the shaft connects to magnets surrounding a coil wire. When the shaft spins the magnets, this generates the voltage int he wire that electrical current. The generator turns the rotational energy into electricity. 


How Nuclear Power works 
Nuclear plants use the heat generated during nuclear fission, when an atom splits and releases energy. Uranium pellets are submerged in water in a pressure vessel. Control rods can be used to produce or reduce heat. The uranium bundle heats the water and turns it to steam. The steam drives the turbine, which spins a generator and makes power. 


Wednesday, February 26, 2014

Circuits at Home


Cost of running light bulb for 8 hours at 22¢ kw/hr


Coffee maker 

Cost of running coffee maker for thirty minutes at 22¢ kW/hr

Thursday, February 13, 2014

IPad Batteries

http://electronics.howstuffworks.com/everyday-tech/lithium-ion-battery1.htm



What was included in the article?
This article talked about how the lithium ion battery works. In explaining the parts of tha battery, it said there was a voltage converter and regulator circuit, which relates to class. This is used to maintain safe levels of voltage. It also explained that there is a postive electrode, a negative electrode, and a separator. When the battery charges, ions of lithium move through the separator from the positive electrode to the negative,and attach to the carbon. These lithium ions move at a very high voltage.

What did I learn in class that helped me to understand? 

Our discussions on voltage helped a lot in understanding this article. It was helpful to know that energy is stored when a charge is placed at a voltage. A voltage being a buildup of charge. It was also helpful to know that in a normal battery electrons are given electric potential energy from the voltage of the battery. This energy is then converted into other forms. The iPad battery also uses a similar process as the iPad will also take the electric potential energy of the electrons and convert it. 


Monday, February 10, 2014

Charge Transfer and Interaction





How did the balloon become negatively charged when rubbed on my hair?
Most everything starts off neutral. When I rub the balloon on my hair, my hair sends electrons to the balloon. The balloon gains electrons and becomes negative while my hair loses electrons and becomes positively charged. 

How does the balloon attract neutral water? 
The hydrogen atoms are positive while the oxygen atoms are negative in a water molecule. The water molecules realign themselves to put the positive towards the negatively charged ballon. The molecules are now polarized, or separated. The stream of water alters it path closer to the balloon as it is attracted to it due to opposite charges. 

Wednesday, January 29, 2014

Projectile Motion lab

In order to demonstrate rpoject motion, we threw a basketball in the air. We videotaped this motion using video physics, and we plotted points along the flight path of the basketball. We were then able to creat graphs with which we examined the projectile motion of the basketball. 

Graph of x velocity 

Mh linear fit equation was y= -1.740 x+ 3.424. Since the slope is relatively close to 0, it is a horizontal line. Since the slope is 0, the acceleration is 0 in the x direction. The object is moving to the left because the velocity is negative. There is no horizontal force, so it is traveling at a constant speed horizontally. The equation is Vx(t)= Vxi. 

Graph of y velocity: 

My linear fit equations was y= -11.336x + 5.245. When the velocity is postive, it is slowing down and moving upward. At Vy= 0, it turns around, and speeds up moving downward due to the negative velocity. The velocity of y is constantly changing with time. The slope is the acceleration due to velocity. 
The equation is Vy(t)= -10m/s2t + Vyi. These graphs always have a slope of -10m/s2 and are never curved. 
Graph of x:

My linear fit equation was y= 2.746x + .089. The slope of x vs t is Vx. The object is moving in the t direction and rightward. The equation is x(t)= Vxt+ Xi. These graphs are never curved because velocity is constant. 

Graph of y:

The equation of my linear fit line was y= 1.139x + .587. The graphs for y are always curved as it demonstrates the flight path. The equation is y(t)= (-10m/s2) t2 + Vyit +Yi.