Sunday, February 27, 2011

RHR 1 and 2

During class we learned about the 2 right hand rules. Right Hand Rule 1 and Right Hand Rule 2

Right Hand Rule 1 states that:
in a conductor when the thumb of the right hand points the direction of the current flow, the fingers will curl in the direction of the magnetic field.

Right Hand Rule 2 states that:
in a coil, when the thumb points to the north of the coil, the fingers curl towards to the current flow

Wednesday, February 23, 2011

Concept map+10 most important things to remember

Today in physics class, mr chung split us into groups and told us to make a concept map using words give to us without talking to one another. Though difficult at first, this experience really showed that in a group, everybody has their own strengths and it is hard to notice it normally because usually only the loud people's ideas get heard.
This is a picture of our concept map:

The top 10 most important things that you need to know for electricity are:\
10)Power: rate at which work is done- P=VI
9)Resistance/Ohm's law: R=V/I
8)Current: the rate at which charges flow - I=Q/t
7)parallel circuit-a circuit in which the loads are parallel to one another
6)series circuit - a circuit in which the loads are connect in one single path
5)conventional current- positive charges that flow
4)e flow- negative charges flows in a circuit form positive terminal to negative
3)voltage-voltage drop across two different points - V=E/Q
2)Q/coulombs-charges
1)Kirchhoff's Law:

For Series:
Current:
It = I1 = I2 = I 3...=In
Potential Difference:
Vt = V1 + V2 + V 3...+Vn
Resistance:
Rt =R1 + R2 + R 3...+Rn

For Parallel Circuit:
Current:
It = I1 +I2 + I 3...+In
Potential Difference:
Vt = V1 =V2 =V 3...=Vn
Resistance:
Rt=1/R1+1/R2+1/R3+1/Rn

Thursday, February 17, 2011

b4/Kirchhoff's Law and Ohms' Law

Today we learned about Ohms law and Kirchoff's law. Ohm's law is that resistance equals to the potential difference divided by the current.

It can be shown by this equation: R=V/I

Kirchoff's Law is:
in a series circuit:
It=I1=I2=...In
Vt=V1+V2+...Vn
Rt=R1+R2+...Rn
in a parallel circuit:
It=I1+I2+..In
Vt=V1=V2=..Vn
1/Rt=1/R1+1.R2+..1/Rn

























Wednesday, February 9, 2011

b3/ fav coster

Today, we did a lab on ohm's law and resistance. In this lab with the help of a resistor who's resistance was 15 +/- 5%, I found out that the resistance = the voltage divided by the current.
The diagram below gives one a clearer understanding of electrical resistance:

On to the second part of this blog...
My favourite rollercoaster is the Behemoth in Canada's Wonderland.
Though many would think that the Behemoth is overrated I think it is the overall best ride in Wonderland.
Below is a picture of the coaster:

Monday, February 7, 2011

b2/current eletricity

February 7th. Today in physics class we each had around 15 minutes to fill in a worksheet on current electricity. Though hard, it is very interesting and a good review of what I learned in grade 9. We then watched a video of how current electricity works. In the video we learned about electrodes, circuits, direct current and alternating current, and the fact that the amount of electrons passing through 1 point in a DC (direct current) in a period of time will equal the amount of electrons passing through any other point in the circuit within the same amount of time. Near the end of the class Mr. Chung explained to us about the mistake of Ben Franklin. The mistake was his idea of current electricity. Ben originally thought that in a circuit, the positive charges transfer but actually it was the negatively charges that moved. Though wrong we still use this as a measurement because it is now too late to change.

Saturday, February 5, 2011

b1/energy ball

As our first lab in grade 11 physics, we experiemented with an energy ball. This energy ball contained a powers source, light bulb and a buzzer. In order for the ball output light and sound, we had to make a complete circuit. With the energy ball, we also recieved a few questions about how it works, how to make it work, etc. To our surprise Mr. Chung gave us a task that required everyone in the class work together and make a parallel circuit including 2 energy balls. We succeded and ended the class with our first lab report. Overall the first physics class is going well.