Blog 24

In this week of Physics we learned about the differences between a series circuit and parallel circuit. Here are the differences:

SERIES:
- 1 path, 1 current
-Vtotal - V1 + V2 + V3 ...
- Req = Rtotal = R1 + R2 ...

PARALLEL
- Constant Voltage
- Ivsource = I1 + I2 ...
- 1/Req = 1/R1 + 1/R2 ...

I also learned that our houses are wired in a parallel circuit. This is good so every appliance, or "resistor" may run using all of the volts it needs. If our houses were wired in a series circuit, then we could only be able to run a few to one thing at a time because everything would have to share a total voltage.

Blog 23

In the previous week of Physics class, we have been talking about saving electricity. I have went home and had a discussion with my dad about saving electricity. He was open to it of course, as it would save him some money, and we thought of a few ways we could do this. Sometimes we fall asleep with several appliances left on. We could save a good deal of electricity by making sure to turn off things before we doze off. There are some days where someone falls asleep and the TV is watching them. Also sometimes the lights are left on all night wasting energy. Another thing I could do is to shorten my showers a bit. I usually take long, hot showers and although relaxing, I could shorten them at least a little bit.

Blog 22

Adding on to Unit 11, we dug further and learned more about electricity. I learned that current is the number of charges passing a point per second, or the rate of flow of charges. Current can be represented by the variable "I" and is measured in Amperes or Amps. One Amp (A) is equal to 1 Coulomb per second (I = q/t). Recapping from last week, voltage is the amount of work that each charge will do as it goes through the circuit; it can be thought of as the amount of "push" on the charge. So voltage is the amount of energy per charge and current is the amount of charge per second. A great example of this are these ceiling lights. Electrons (charges) are carrying energy (joules) and are passing through the lightbulb. As each electron passes through the bulb, it drops off and supplies a constant flow of energy, allowing the bulbs to stay lit.

Blog 21

In this last week of Physics class, one very important topic we learned about was of capacitance. Capacitance is the ability of a capacitor to store energy in an electric field. It's also the storage of energy (short term). Capacitors are able to store of lots of VOLTAGE, but not a great deal of charge. A great example of a capacitor is a cloud. When there is enough volts are built up and stored within the cloud, it releases all of its volts and releases lightning. The ground and cloud act as parallel plates so the lightning can reach across and transfer its charge.

Blog 20

In this week of Physics we learned about Electric Potential. One of the most important things to keep in mind is that Electric Potential is NOT the same as Electric Potential Energy. Electric Potential Energy is measured in Joules, (a unit of energy). Electric Potential is measured in Volts. Volts are equal to Joules/Coulomb or energy per unit of charge. Volts should be thought of as a “Push” while Electric Potential Energy (PEq) can be thought of as how long something can keep going. For example, look at this power outlet. Say its Electric Potential is 120 Volts. This means that it has a “push” of 120 Joules per Coulomb. The more Joules (PEq) the power outlet has, then the longer it’s able to give energy.

Blog 19

In this last week of Physics, we further explored Electrical charges. I have learned that like charges repel, while unlike charges attract. For example, two "-" charges or two "+" charges would repel while a "+" and "-" charge would attract. Also, a neutral charge would attract to either a "+" or "-" charge. Another important concept that I learned was of the equation q = ne-. This is the Coulombs law and is used to find the charge of something. q represents charge and is equal to the product of n (the # of charges: protons or electrons) and e- (the charge of 1 electron: 1.6 x 10^-19).

Blog 18 Q3

In this week's Physics lessons, we were introduced to electrical charges of objects. There are three types of charges an object can have: positive (+), negative (-) or neutral (o). The charges are based on how many electrons an object has. Generally, objects are neutrally charged, but as electrons are transferred, objects gain a positive or negative net charge. If an object gains electrons, there would be more electrons than protons thus the object would be negative overall. If an object were to lose electrons, the object would be positively charged because there would be less electrons than protons. A great example of this is a piece of tape. It's neutrally charged, but when placed on surface (desk) and ripped off quickly, the friction causes the transfer of electrons and causes the piece of tape to have a charge.