Unit 6 Reflection

This unit in physics we learned about charge, polarization, and electric fields! We learned how real life situations such as hair standing up after pulling a sweater over it, or why a balloon sticks to a wall after rubbed against hair, is so.

Charges:

Charges are such by the make up of protons (positive ions) and/or electrons (negative ions). Protons and electrons attract each other while protons and protons or electrons and electrons repel each other. There are three ways that an object could be come charged: friction, direct contact, and induction. When you pull a sweater over your head, the sweater steals electrons from your hair through friction. When this happens your hair is filled with protons, since protons and protons repel each other, your hair stands up!

Polarization:

When discussing polarization, it is important to recognize what a conductors and insulators are. Conductors let charges move through them, insulators stop charges from moving. An object becomes polar when the charges are separated. For example, if you stuck a rod of electrons near a neutral object, all of the protons would move closer to the rod and the electrons would move further away from it. When the negative and positive ions are separated like this, the object is polarized. This is the reason that saran wrap wont stick to metal bowls. Metal is a conductor and will send all charges to the ground whereas glass and ceramic bowls will polarize.

We applied all that we learned about electricity to everyday usage. We learned about lightning rods, light bulbs, circuit breakers, outlets, and more!

Lightning rods:

We learned that lightning rods protect structures because of their ability to prevent fires by their ability to send charges from lightning to the ground. Lightning rods are pointy metal rods that are placed on the roofs of buildings. Protons collect of the points of the rods and when lightning strikes they attract the negatives charges coming towards the ground from the clouds. When the lightning strikes the rods all the charges are send to the ground through a cable that is connected to the bottom of the rod and the ground.

Light Bulbs:

One of the many labs we did this unit required us to light a light bulb using only a battery and some wire. Through this lab we learned that the wire must be connected to the bottom of the bulb and the side of the bulb. These two places are where the wires need to be in order to complete the circuit and light the bulb. Similarly we learned that the wire in the middle of the bulb is called the filament. Based on thickness and length the filament will have either a high or low resistance and will determine how much current can run through it, affecting how bright the bulb is.

Circuit Breakers:

In this unit of physics we learned why circuit breakers commonly trip when you use too many appliances. Circuit breakers are wired as series circuits, which mean as more things are used the current remains the same, while the resistance increases. On the contrary houses are wired in parallel so when you use more appliances, the overall current being used increases. When this current gets too high it could potentially start a fire. In order to prevent a fire from happening, the circuit breaker trips. The circuit breaker flips a switch in the circuit and stops all appliances from working.

Outlets:

This unit we learned about voltage and how our outlets in America are 120-volt outlets. We learned that outlets in Europe have a higher voltage so when we take our appliances to Europe using them is actually dangerous because our appliances are not designed to handle the amount of volts that European outlets emit.