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.

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. 

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. 

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

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. 

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. 

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. 

Forces in Two Dimensions

• How do we analyze forces in 2-Dimensions?                                                                         We can analyze forces in two dimensions by analyzing each dimension separately. We use the x or horizontal dimension and the y or vertical dimension. In order to analyze the dimensions separately, we can use trigonometry. We use fx= F cos theta and fy= f sin theta. You get the net force for each dimension when you add the vertical and hortizontal components separately. 
• How do forces cause objects to move in a circle?                                                   Centripetal force is any force that causes and object to move in a circular motion. The centripetal force is a center-pointing net force, which causes the object to move in a circle. The object can move at constant speed, but it is constantly changing direction. 
• What does it mean to be in orbit? How do satellites orbit planets? How do planets orbit the sun?                                                                                                                                           To be in orbit means that one object is on a continuous elliptical path around another object in space. Satellites orbit planets because an object will stay in motion unless and unbalance force acts on it. The force of gravity pulls the satellite towards the earth. The satellite is actually falling around the earth because as the earth curves, the satellite curves. It must be in orbital velocity. Planets orbit the sun because of the centripetal force of gravity that comes from the sun. There is no other force in the solar system to keep them from orbiting. The earth orbits at a constant speed, but it is accelerating because the direction of it's velocity is constantly changing.