Week 2: Ohm's Law

"Ohm's Law"

-Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. Introducing the constant of proportionality, the resistance, one arrives at the usual mathematical equation that describes this relationship:

where I is the current through the conductor in units of amperes, V is the potential difference measured across the conductor in units of volts, and R is the resistance of the conductor in units of ohms.

Ohm's Law triangle:

In our 2nd week, We also discussed the two types of elements that are in an Electrical Circuit. These are Passive Elements and Active Elements.

Active Elements- These elements generate energy. Examples are Batteries, generators, and operational amplifiers.

Passive Elements- These elements drop energy. They cannot generate energy because they take energy from a circuit. Examples are Resistors, Capacitors, and Inductors.

Also in our 2nd week, We also discussed the following: Open Circuits and Short Circuits.

Open Circuit- is a condition in an electric circuit in which there is no path for current between two points; examples are a broken wire and a switch in the open, or off, position.

Short Circuit-  is an electrical circuit that allows a current to travel along an unintended path, often where essentially no (or a very low) electrical impedance is encountered.

In our 2nd week, We also discussed Conductance. Conductance is

- An expression of the ease with which electric current flows through a substance. In equations, conductance is symbolized by the uppercase letter G. The standard unit of conductance is the siemens (abbreviated S), formerly known as the mho.

When a current of one ampere (1 A) passes through a component across which a voltage of one volt (1 V) exists, then the conductance of that component is 1 S. The siemens is, in fact, equivalent to one ampere per volt. If G is the conductance of a component (in siemens), I is the current through the component (in amperes), and E is the voltage across the component (in volts), then:

Reflection:

In our 2nd week of CpE 311, I learned that there is another way to identify if a component in a circuit is a passive element or an active one. In our previous lesson, Sir Jay taught us that if the current enters a negative terminal and then exits a positive terminal, then the component is an Active Element. Otherwise, if the current enters a positive terminal and exits a negative terminal, then the component is a Passive Element. Also in our previous lesson, He explained to us Ohm's  Law with the following illustration:

In this illustration, A man is pushing a table. With relation to newton's 2nd law of motion, The force that the man exerts to make the table move is the "Voltage", the movement of the table is the "Current", And the friction that resists the movement of the table is the "Resistance".

Ohm's Law

Active & Passive Elements:

Once again, Thank you for visiting my Blog. The third post will be arriving next week :D.

About the author:

Roswaldo S. Flores BSCpE-3

CpE 311

Instructor:

Engr. Jay S. Villan, MEP

Week 1: Basic Electrical Circuit Concepts

HI! I am Roswaldo Flores and this is MY BLOG. WELCOME!!

This Blog is a summary of all the things I have learned from Sir Jay S. Villan and at the same time, It is also a pre-requisite in our CpE 311 Subject. Thank you for visiting my blog and please enjoy reading it. :)

The Basic Parts of an Electrical Circuit:

Power Source – The Power Source is where the electricity comes from. It is sometimes called as “source of emf”, refers to a generator, a battery of cell or a transmission power line.

Conductor – Conductors are materials that deliver energy to power a task.

Load – Load are devices that consumes electricity on its operation. 

An Electric Circuit will not work if one of the said parts are missing.

Charge:

- there are two kinds of charge, positive and negative.

- like charges repel, unlike charges attract.

- positive charge comes from having more protons than electrons; negative charge comes from -  having more electrons than protons.

- charge is conserved.

Current - is the rate at which charge flows past a point on a circuit. It is measured in "Amperes" (A).

Electric Power or simply called "Power" - is the rate of energy consumption in an electrical circuit.The electric power is measured in units of "watts" (W).

Voltage - is electric potential energy per unit charge, measured in joules per coulomb ( = volts) (V). It is often referred to as "electric potential", which then must be distinguished from electric potential energy by noting that the "potential" is a "per-unit-charge" quantity.

Electrical energy or simply called "Energy" - is the energy carried by moving electrons in an electric conductor.  It cannot be seen, but it is one of our most useful forms of energy because it is relatively easy to transmit and use. It is measured in "Joules" (J).

3 Basic Circuit Elements:

1. Active Elements- These Elements are capable of generating energy. Examples are Batteries, Generators, and etc.

2. Passive Elements- These Elements are capable of absorbing energy. Good examples are Resistors, Inductors, and many more things.

3. Voltage and Current Sources- These are the most important active elements and just like the name says, they generate Voltages and Current which in turn can be used by Active Elements to generate energy.

Video:

Reflection:

CpE 311 is a fun and exciting subject. Sir Jay seems to be a strict teacher for me but I enjoy listening to him He had a sense of humor unlike a majority of other teachers and he explains his lesson well. He taught us many things. H taught us the basic concepts of Electrical Circuits and He even gave us a quiz. The quiz he gave was difficult and it was different from what I copied in the black board. I didnt even do well and I'm pretty sure that my marks for that one was low. Nevertheless, He taught me one thing that I will always remember: He taught us that we shouldnt just depend on him, He told us that we should explore things and by that I meant Try other problems that were not discussed. He taught us to not just depend on the knowledge that are already written in our notebooks, He taught us to look for it and to improve it. After all, Knowledge is not acquired by simply writing things down, Its acquired by finding out many things and understanding them. I thank him for he is about to give me a wonderful and bright future.

Thank you for visiting my Blog!! I will be regularly updating this every week. 

See you later :D

About the Author:

Roswaldo S. Flores BSCpE-3

CpE 311

Professor:

Engr. Jay S. Villan, MEP