Science 9 - Unit 3 - Characteristics of Electricity

What is grounding?

Allowing charge to flow into Earth's surface is called grounding. Earth is so large it can accept charges without becoming charged itself.

What is the unit for electric current?

Amperes.

What is an ammeter?

An ammeter is a device used to measure the current in a circuit.

What is an electric load?

Any device that transforms electrical energy into other forms of energy is called an electric load. ex. lightbulb

What do electrochemical cells do?

Electrochemical cells convert chemical energy into electrical energy stored in charges. Electrochemical cells are commonly called cells or batteries.

An electric force is an example of an...

Action a distance force.

What are the laws of static charge?

• Like charges repel. • Opposite charges attract. • Neutral objects are attracted to charged objects.

What are the 4 parts/components in a circuit?

• Source: the source of electrical energy • Conductor: the wire through which electric current flows • Load: a device that transforms electrical energy into other forms of energy • Switch: a device that can turn the circuit on or off by closing or opening the circuit

The amount of voltage that is produced in an electrochemical cell depends on...

...the types of metal and the electrolyte used. :)

Electrons in a circuit have (blank) potential energy after traveling through the load.

0. :)

How are resistors marked?

1st digit 2nd digit x 10ª Accuracy (%)

What is a battery?

A battery is a combination of electrochemical cells connected together (or a single electrochemical cell).

What is a series circuit?

A circuit that has only one path for current to travel is called a series circuit. In other words, electrons have only one pathway to travel through a series circuit. If the switch is opened, all electrons are blocked and the current stops.

What is a parallel circuit?

A closed pathway that has several different paths is called a parallel circuit.

What is an electric circuit?

A complete pathway that allows electrons to flow is called an electric circuit.

What is an ohmmeter?

A device that measures resistance! :)

What is a kilowatt- hour (kW•h)?

A kilowatt- hour (kW•h) is the product of power in kilowatts and time in hours. 1.0 joule = 1.0 watt x 1.0 second 1.0 kilowatt-hour = 1.0 kilowatt x 1.0 hour

What is a power rating?

A power rating is a measurement of how much electrical energy an electrical device consumes for every second it is in use.

What is force?

A push or a pull!

What is a resistor?

A resistor is an electrical component that has a specific resistance. Resistors can be used to control current or potential difference in a circuit to provide the correct voltage and current to the other components of the circuit.

What is an electrolyte?

A substance that conducts electricity. In a dry cell, the electrolyte is a moist paste; in a wet cell, the electrolyte is a fluid.

What is a voltmeter?

A voltmeter is a device that measures the amount of potential difference between two locations of charge separation. When you place the connecting wires of a voltmeter across the + and - terminals of a battery, the voltmeter displays the battery's voltage.

How do you calculate energy consumption?

By using the power rating and the amount of time, you can calculate the amount of electrical energy a particular device consumes. Power (P) is defined as energy transferred (E) per time interval (t) in seconds. Therefore, P = Et

What is charging by conduction?

Charging a neutral object by touching it to a charged object is called charging by conduction.

What is a circuit diagram?

Circuit diagrams are diagrams that use symbols to represent the different components of the circuit.

If you increase the distance between charged objects, you (blank) the electric force.

Decrease!

The total resistance of the circuit is (blanked) when resistors are placed in parallel.

Decreased, meaning that the potential energy from the battery must increase.

What is electric current?

Electric current is defined as the amount of charge passing a point in a conductor every second.

What is electrical power?

Electrical power is the rate of change in electrical energy. An electrical load changes electrical energy to other forms. The amount of electrical energy changed or transformed on a load per second is the power rating of the load. For example, a 60 W light bulb uses 60 J of electrical energy every second and produces 60 J of heat and light energy

What is electrical resistance?

Electrical resistance is the ratio of the voltage to the current.

What is energy?

Energy is the ability to do work.

How do you calculate electrical power?

For calculating the power of an electrical device, it is more common to talk about the voltage and current rather than energy and time. You can calculate the power of an electrical device by multiplying voltage and current. In other words, electrical power (P) is the product of voltage (V) and current (I): P = VI.

What are some other main sources of electrical energy other than batteries?

Friction - Piezoelectric crystals - used in barbecue lighters Solar Panels (Photo-electrochemical cells) Thermocouples - used in ovens, those glowing wires Generators - used in most of our home appliances ex. hydroelectric energy

What is charging by induction?

If you bring a negatively charged object near, but not touching, the knob of the electroscope, the negative charge will repel the electrons in the knob. The electroscope is a conductor, so the electrons will move down to the leaves (Figure 7.12). The leaves of the electroscope will have a temporary negative charge and will repel each other. The knob will be positively charged. This is called charging by induction. If you move the charged object away, the leaves will go back to their original position. *** *** IF you don't understand look at page 260 in the text it really helps :)

If you decrease the distance between charged objects, you (blank) the electric force.

Increase!

What are conductors?

Materials that allow electrons to travel freely are called electrical conductors.

What are insulators?

Materials that do not allow charges to move easily are called electrical insulators.

What is potential energy?

Potential energy is the energy stored in an object. The electrical energy stored in a battery is called electric potential energy because the electrons have a stored energy and the ability to do work after they leave the battery.

What is power?

Power is defined as the rate of change in energy. Power is also the rate at which work is done or energy is transformed.

What is resistance?

Resistance is the property of any material that slows down the flow of electrons and converts electrical energy into other forms of energy.

What is static charge?

Static charge, also known as static electricity, refers to electric charges that can be collected and held in one place.

What are electrodes?

The 2 terminals in a battery. :)

What does the Van de Graff generator do?

The Van de Graaff generator uses friction to produce a large static charge on a metal dome. A moving belt produces a static charge at the base of the generator. The belt carries this charge to the top where it collects on the dome.

What is potential difference or voltage?

The amount of electric potential energy per one coulomb of charge is called the potential difference or voltage. The unit for measuring potential difference is the volt (V).

What is the unit of electrical charge?

The coulomb!

What can friction between two objects cause?

The friction between two objects can result in one object losing electrons and the other object gaining electrons.

What is a junction point?

The location where a circuit divides into multiple paths or where multiple paths combine is called a junction point.

What is a joule?

The unit for measuring energy is the joule (J). One joule (J) of energy transformed in one second (s) is called one watt (W) of power.

What is the unit of measurement for electrical resistance?

The unit of measurement for electrical resistance is the ohm . The mathematical relationship comparing voltage (V), current (I), and resistance (R) is called Ohm's law and is written as: R = V/I Ohm's law is more commonly written in the form: V = IR You can use Ohm's law to calculate resistance.