In the motors we assembled in class, we used a specific and limited set of materials: a battery, two paper clips, a small magnet, rubber bands, and a copper wire. Each of these objects served as part of a larger mission to get the wire to spin.
The battery serves as a charged object, and the paper clips carry the charges to the copper wire. The wire is scraped on one side on each end allowing the current to get through. The magnet rests on top of the battery, attracting the charges of the copper wire, causing it to spin. Lastly, the rubber bands keep the paper clips connected to the battery.
The motor turns because of its interaction with the magnet on top of the battery and the magnetic field that it puts off. The total force of this object is going up, and into the loop, forcing it to move.
This motor could be used as a small fan, maybe for a mouse in the summer. Blades could be attached to the ends of the wire, and the wire would continue to spin, creating a fan.
Friday, April 24, 2015
Tuesday, April 14, 2015
Electricity
In this unit, the overarching theme was electricity. We began with static electricity found in winter caps and laundry without drier sheets. We learned that there are three types of transfer: friction, contact, and induction. Before we could fully understand what happens in these situations, we had to refresh our memories about protons, electrons, and how they interact with each other. We then discussed electric fields and shielding, with the example of why electronic devices are kept in metal cases. From there, we talked about capacitors and electric potential. Ohm's Law followed that, where we learned about the relationships between current (I), voltage (V), and Resistance (R). Using our knowledge of current, we learned about the different types of circuits and how electrons play into that.
Charges and Polarization
A big question that we answered in class was why your hair sticks up when you take off a hat in the winter. Knowing that electrons are negative and protons are positive, we were able to understand that like charges repel, and opposite charges attract each other. The friction of the hat causes the hat to steal the electrons, and make all of the hairs on your head positive. Because like charges repel, the hair separates and stands up. There are three ways that energy can transfer: friction, contact, and induction. Friction is the rubbing of two charges objects, contact is touching, and induction is the action of something being charged without touching it. Polarization is related to Coulomb's law which is F=kq1q2/d^2. When a charged object contacts a neutral object, the neutral objects charges separate so that the charged object can react with it. This is the topic where we recapped on the inverse square law.
Electric Fields
My group did our podcast on this topic, and we focused a lot on Coulomb's Law and why electronics are cased in metal containers. This is because of the neutral electric field that the device must maintain. Electronics have circuit boards that require all charges to stay in their assigned locations. The metal case protects the charges from influence, and allows the whole device to remain neutral and feel no force.
Electric Potential/ Capacitors
The main question we were asked in this sub-unit was why photos cannot be taken as rapidly when the flash is on. This is because the flash acts as a capacitor which means that within the device there are two oppositely charged plates. They continue to gain charges through energy, and once they gain enough charge, they connect briefly. This connection results in a release of energy in the form of light and sound. Because this process takes so long, it is hard for the flash to work as continuously as a camera without flash. Also during this sub-unit, we tackled the meaning of two different terms that sounded very similar. Electric Potential Energy is stored energy in charges, while Electric Potential is the Electric Potential Energy/Charge.
Ohm's Law
Through a lab, we learned that Ohm's law is I=V/R. While we understood how to substitute values into the variables, it was a good refresher of which variables were directly or inversely proportional to each other. Current and Voltage are directly proportional, while Current and Resistance and Voltage and Resistance are inversely proportional to each other.
Current, Power, Electrons
The two types of wiring that we discovered were parallel and series. Parallel circuits are the most common, while series circuits are found in fuses, and the notorious christmas light problem. An important formula that we learned was that power=current(voltage) or P=IV for short. Parallel circuits allow one source to go out and all of the others stay on. However, series circuits all rely on one source to keep many lights on.
Charges and Polarization
A big question that we answered in class was why your hair sticks up when you take off a hat in the winter. Knowing that electrons are negative and protons are positive, we were able to understand that like charges repel, and opposite charges attract each other. The friction of the hat causes the hat to steal the electrons, and make all of the hairs on your head positive. Because like charges repel, the hair separates and stands up. There are three ways that energy can transfer: friction, contact, and induction. Friction is the rubbing of two charges objects, contact is touching, and induction is the action of something being charged without touching it. Polarization is related to Coulomb's law which is F=kq1q2/d^2. When a charged object contacts a neutral object, the neutral objects charges separate so that the charged object can react with it. This is the topic where we recapped on the inverse square law.
Electric Fields
My group did our podcast on this topic, and we focused a lot on Coulomb's Law and why electronics are cased in metal containers. This is because of the neutral electric field that the device must maintain. Electronics have circuit boards that require all charges to stay in their assigned locations. The metal case protects the charges from influence, and allows the whole device to remain neutral and feel no force.
Electric Potential/ Capacitors
The main question we were asked in this sub-unit was why photos cannot be taken as rapidly when the flash is on. This is because the flash acts as a capacitor which means that within the device there are two oppositely charged plates. They continue to gain charges through energy, and once they gain enough charge, they connect briefly. This connection results in a release of energy in the form of light and sound. Because this process takes so long, it is hard for the flash to work as continuously as a camera without flash. Also during this sub-unit, we tackled the meaning of two different terms that sounded very similar. Electric Potential Energy is stored energy in charges, while Electric Potential is the Electric Potential Energy/Charge.
Ohm's Law
Through a lab, we learned that Ohm's law is I=V/R. While we understood how to substitute values into the variables, it was a good refresher of which variables were directly or inversely proportional to each other. Current and Voltage are directly proportional, while Current and Resistance and Voltage and Resistance are inversely proportional to each other.
Current, Power, Electrons
The two types of wiring that we discovered were parallel and series. Parallel circuits are the most common, while series circuits are found in fuses, and the notorious christmas light problem. An important formula that we learned was that power=current(voltage) or P=IV for short. Parallel circuits allow one source to go out and all of the others stay on. However, series circuits all rely on one source to keep many lights on.
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