Electricity

Find Energy Efficiency: Volume: 210 mL of water Initial Temperature: 22°C Final Temperature: 94°C Electrical energy absorbed: 27 calories/minute Time: 700 minutes Flourescent Light Efficiency = %

20%; 1)Thermal Energy Released= Mass(Water) x Temperature change(Water) 2)Electrical Energy Absorbed= Time bulb is lit x energy burned/minute 3)Thermal Energy Output(%)= Thermal energy released/electrical energy absorbed x 100% 4) Light efficiency(%)= 100%- Thermal Energy Output

Conductors

Aluminum, carbon rod, copper, iron,magnesium

Electrons

Always carry negative charge

Protons

Always carry positive chargr

Describe an atom

An atom is built with a combination of three distinct particles: electrons, protons, and neutrons. Each atom has a center nucleus, where the protons and neutrons are densely packed together. Surrounding the nucleus are a group of orbiting electrons.

Electric Current

As our free electron is floating in a space between atoms, it's pulled and prodded by surrounding charges in that space. In this chaos the free electron eventually finds a new atom to latch on to; in doing so, the negative charge of that electron ejects another electron from the atom. Now a new electron is drifting through free space looking to do the same thing.This chain effect can continue on and on to create a flow of electrons called electric current.

Series

Charge flows through each component along a single path of current

Paralell

Components are connected to the same two points of a circuit providing multiple pathways for the path of current

What are the three required components to a functional alarm/any functional circuit?

Components of a circuit include -a voltage source -wire conductor -device which uses the energy

In order for an electromagnet to have a magnetic field it must be

Connected to electrical source

Current Electricity

Current electricity is the form of electricity which makes all of our electronic gizmos possible. This form of electricity exists when charges are able to constantly flow. As opposed to static electricity where charges gather and remain at rest, current electricity is dynamic, charges are always on the move.

If the current through a coil of wire is decreased, the magnetic field strength of the wire coil will

Decrease

Magnetism can be created using...

Electricity

What is electricity? How does it rely on the atomic structure?

Electricity is the flow of electric charge. This occurs because of the electrons in the atoms.

Free Electrons

Electrons that escape the orbit of an atom

What 2 forms does electromagnetism take?

Electrostatic force and magnetic force

Electricity

Flow of electric charge

Explain what it means for a lightbulb to be efficient?

For a lot of the energy to be transferred into light energy.

Electrostatic Force

Force that exists between positive and negative charges. Opposites attract and likes repel.

Neutrons

Have no charge

What does electrostatic force cause?

Lightning

Electricity can be generated by...

Magnetism

Magnetic fields have both a negative and a positive area: ___________ and ____________

North and South

Lightning

One of the most dramatic examples of static discharge is lightning. When a cloud system gathers enough charge relative to either another group of clouds or the earth's ground, the charges will try to equalize. As the cloud discharges, massive quantities of positive (or sometimes negative) charges run through the air from ground to cloud causing the visible effect we're all familiar with. Static electricity also familiarly exists when we rub balloons on our head to make our hair stand up, or when we shuffle on the floor with fuzzy slippers and shock the family cat.

Would you prefer your entire house to be wired in series or parallel? Why?

Parallel because when one light goes out the rest are still able to be on.

Circuit

Path of an energy transfer. A closed, never-ending loop of conductive material.

What charge does the copper coil have? How do you know?

Q

Charge

Ratio of protons to electrons. The key concept with charge is that it can come in two types: positive (+) or negative (-).

Energy Efficiency

Ratio of useful energy to the total energy

Electrostatic force and magnetic force are one in the...

Same

Static Electricity

Static electricity exists when there is a build-up of opposite charges on objects separated by an insulator. Static (as in at rest") electricity exists until the two groups of opposite charges can find a path between each other to balance the system out.

What's the difference between static and current electricity?

Static electricity is where charges gather and remain at rest, whereas current electricity is dynamic, charges are always on the move.

What are the variables that affect the speed at which a motor will turn?

Voltage (number of batteries) Distance between magnet and coil Strength of magnet

Static Discharge

When the charges do find a means of equalizing, a static discharge occurs.The attraction of the charges becomes so great that they can flow through even the best of insulators (air, glass, plastic, rubber, etc)

Which materials can be used as the conductor in a circuit?

Wire(?)

How did this lab(Lesson 4.2 energy efficiency) demonstrate the Law of Energy Conservation?

You can

Photons

carry the electrostatic force between the electron and proton