electricity ****

A circuit has total resistance of 5 ohms and a current of 0.3 amperes. The voltage the battery must supply is volts.

1.5

You are using an electric motor which requires 40 volts to operate. The motor's circuit uses only 5 amps of direct current. The power is being used is watts.

200

A 24-volt doorbell carries a current of 6 amperes. The resistance in the bell is ohms.

4

Alternating current cycles back and forth (changes direction) times per second in the U.S.

60

The process by which written or printed material is copied using static electricity is .

xerography

How does an electrostatic generator operate?

Electrons are stripped off a wool pad. Electrons are transferred to a metallic sphere.

induced currents

Faraday

The force that pushes electrons through a wire is called .

electric potential

A large electrostatic generator is commonly called a(n) generator.

van de whatever fam

The standard measure (unit) of electromotive force is .

volt

unit of electromotive force or electrical potential

volt

The device that demonstrates the presence of static electricity is called a(n) .

electroscope

Resistance to the flow of electrons in a conductor causes a loss of as heat.

energy

An electrical wire with low conductivity will have low resistance.

false

It is safe to stand under a tall tree when lightning is present in the area.

false

Metals have tightly bound outer electrons.

false

Protons and neutrons are involved in electric currents.

false

Electromotive force is usually provided by a(n) _____ or _____ in an electric circuit.

generator, battery

The quantity of electrical current in a circuit depends upon which factors?

voltage, ohms

The power used by an electrical tool or machine can be determined by multiplying the _____ and _____.

volts, amps

The metric unit of electrical power is the _____.

watt

Which of these characteristics would be true of a conductor?

high conductivity, low resistance

Heating devices can be made by passing an electric current through a conductor of:

high resistance, low conductivity

Which of these characteristics would be true of an insulator?

high resistance, low conductivity

As the total resistance is reduced in a simple electrical circuit, the current flow will _____.

increase

A substance that prevents an electric current is a(n) _____.

insulator

A charged atom is a(n) .

ion

An atmospheric discharge of static electricity is called .

lightning

Why are lightning rods effective?

lightning often will discharge on objects which stand above the surroundings

the resistance to water flow in a rough or partially clogged pipe is like a conductor having _____.

low conductivity

If a simple circuit connected to a battery had its wires replaced with thinner (finer) wires, what would the ammeter read?

lower

Why has alternating current been preferred for many years?

more efficient transmission, less energy loss during transmission

unit of electrical resistance

ohm

The flow of electricity can be compared to the circulation of water in a(n) system.

open

An atom that loses electrons is charged _____.

positively

The rate at which energy is used is called .

power

Objects with like charges _____.

repel each other

The electrical charge you accumulate from a nylon carpet in the winter is an example of electricity.

static

What happens to an electric charge which a lightning rod receives from a strike?

the lightning is discharged into the ground

What causes an electric charge to jump from your hand to a metal object?

the metal object conducts electricity, your hand conducts electricity, your feet and body accumulated an electric charge

An atom is electrically neutral.

true

Benjamin Franklin invented lightning rods to protect buildings from lightning.

true

Like magnetism, static electricity can attract and repel.

true

A circuit carrying current in one direction is called a(n) current circuit.

direct

A direct-current generator is called a .

dynamo

alternating current electricity

Westinghouse

A substance that permits the flow of electrons is a(n) _____.

conductor

Of the following choices, the best conductor is _____.

copper

magnetism/electricity

Oersted

batteries

Volta

In the math equation for Ohm's Law, I represents __ and R represents __.

amps, ohms

Static electricity is produced when _____.

atoms gain or lose electrons

in order for electric current to flow, an electric circuit must be _____.

closed

when you turn on a television, the electrical circuit _____.

closes

The measure of the ease or difficulty of current flow for a material is called _____.

conductivity