Color

This is a picture of a plant. The flowers and the leaves show physics. The physics of color and light. Light that shines from the sun is white light made up of red, green, and blue. When a object looks a certain color it is because one or more of the parts of light are being either reflected or absorbed. In the flowers, the petals are white which mean that all the colors of light are being reflected. The inner part of the flower is yellow which means that blue is being absorded while green and red are being reflected which creates the yellow which you see. The leaves and stems which are green are formed by the absorbtion of red and blue while only green is reflected which is the color you see. In the bottom right corner of the picture you can see a little bit of a purple flower from a different plant. Purple is a combination created from the absorption of green and the absorption of green. The blue and red reflected will create magenta ideally but if more blue is reflected then the color perceived will be purple.

The Doppler Effect

I know this post is really late but here it goes anyway. This is a picture of my car steering wheel. From this wheel comes the power to blast a very loud car horn. This horn involves the Doppler Effect. The Doppler Effect involves the "perceived" change that a listener observes in frequency and wave length. As the object producing the sound (car horn) is moving toward the listener, the waves of sound increase in frequency as the waves are compressed with shorter wavelengths which gives the impression of a higher pitch horn. As the horn moves away from the listener the sound becomes a lower pitch as the waves emitted from behind the source have a lower frequency and longer wavelengths. This is the Doppler Effect.

yeah I was tired and its an old meter

This past week in class we learned a little about motors, more specifically ac or alternating current motors. These motors use magnets and torque in order to spin a wheel that powers an object. In an ac motor two magnets are placed away from each other creating north and south poles. In between the magnets is the motor which is usually made up of finely woven wires that can be magnetically charged. The third item that is needed is a battery or electric source for power. When the motor is running the motor is being charged by the magnets and, with the electricity moving through the motor, current is flowing in a certain direction. When the motor turns it switches sides but the current always goes in the same direction. Since this happens the motor should flip back the same way so in order to counter that there are many magnets placed so that the attraction force is always there making the motor spin. This is a picture of my garage door opener. It uses an ac motor to open my garage door and although you can't see it from this picture, it is connected to a power outlet on the roof of my garage. This is an example of how we use magnets in our everyday lives.

I can see the light

This past weekend was Presidents Day weekend and i went to a beachouse so i didnt do any homework. I came up with this idea for my blog because i turn on and off lights everyday and i understand now that it is physics. Lightbulbs are made out of glass on the outside and on the inside are wires and metal that are attached to the bottom and side of the bulb base. These two wires at the bottom and side carry a flow of electrons from a power source like a battery. In the middle of the bulb is a filament made out of tungsten which is coiled super tight and then coiled against for a long and small space for the electrons to go. While the electrons flow across the filament they bump into each other and create heat which is so intense that it burns a bright light. This is the light that we see when we turn on lights and also why lightbulbs are very hot to the touch after they have been on for a while. The majority of the heat stays inside the bulb because glass is very resistant to heat so it holds it within. I never knew that so much stuff in life could be related to physics.

In class on Friday we learned about voltage and a little about electrical sockets and how they carry voltage. Voltage is a ratio of potential energy to charge measured in volts. Potential energy is measured in joules and charge in coulombs. Although different objects may have relatively similar voltage, the way people feel the shock is dependent on how many coulombs of electrons are carrying the charge of the voltage. An example of this could be a Van de Graaff and power lines. We learned that power lines have a voltage of around 500,000 volts and a Van de Graaff has a voltage of around 400,000 volts. The feeling that we feel from the two are completely different because of the number of coulombs carrying the energy. In a Van de Graaff there are about a millionth of a coulomb while power lines have an infinite amount of coulombs. So in the Van de Graaff you only feel around half a joule of energy while you feel a whole lot more from power lines. The same goes for electric sockets in comparison to the Van de Graaff where there are not as many coulombs carrying the joules so you dont feel a killer shock.

Static Electricity

I know that this is a lame picture but it was the only thing physics related on my computer. This is a picture of carpet. As we learned in class static electricity can be generated from shuffling our feet across it with socks on. When we shuffle our feet we are charging by friction. In charging by friction, when two materials rub against each other one of the materials will want electrons more than the other. In the case of our feet and the carpet, the carpet wants electrons more than our feet and so we become positively charged. After we are charged and we touch something like a doorknob or someone else sometimes we get shocked. This is due to a want for our bodies to become neutral again so some electrons from the doorknob or person flows to us resulting in a shock and affter we get shocked we become neutral again.