Electricity, Chapter 7 - whole chapter

In which type of circuit are there two or more branches for current to move through? A) open B) uniform C) parallel D) series

C. Parallel The advantage to using parallel circuits is that individual parts can be turned off without affecting the entire circuit.

The law of conservation of charge states that __________. A) charge is not created or destroyed or transferred from object to object B) the mass of all substances present before a chemical change equals the mass of all the substances remaining after the change C) electric charge is not created or destroyed D) charge can be created and

C. The law of conservation of charge states that electric charge is not created or destroyed.

The process of transferring charge by touching is called __________. A) covalent charging B) charging by contact C) electron exchange D) charge conveyance

C. charging by contact The process of transferring charge by touching is called charging by contact.

Which of the following actions increases the resistance of a wire? A) making it shorter B) making it thicker C) making it longer D) decreasing the temperature

C. making it longer The longer the wire, the greater its resistance.

Elements that are shiny and good conductors of electricity are __________ . A) metalloids B) colloids C) metals D) nonmetals

C. metals The best conductors of electricity are metals.

What exerts the force that causes other electric charges to move? A) insulators B) the electric field C) electrical poles D) conductors

C. the electric field Any charge placed in an electric field will be pulled or pushed by the field.

Electric charges flow from __________. A) low-resistance areas to high-resistance areas B) insulators to conductors C) low-voltage areas to high-voltage areas D) high-voltage areas to low-voltage areas

D) high-voltage areas to low-voltage areas Charges flow from high-voltage areas to low-voltage areas.

What is the current in a circuit if the voltage difference is 15 V and resistance is 15 W? A) 0.0 A B) 225 A C) 30 A D) 1.0 A

D. The difference is 1 A.

Electric current in a circuit is measured in _________. A) ohms B) watts C) volts D) amperes

D. amperes Current is measured in amperes.

According to Ohm's law, as the resistance in a circuit __________, the current __________. A) increases, remains constant B) decreases, decreases C) increases, doubles D) increases, decreases

D. increases, decreases Ohm's law states that as the resistance in a circuit increases, the current decreases.

The rate at which electrical energy is converted to another form of energy is called __________. A) hydroelectricity B) energy transformation C) transmission D) electrical power

D.Electrical power is the rate at which electrical energy is converted to another form of energy.

static electricity

the acculumlation of excess electric charge on an object

Which of the following statements about electric charges is true? A) Electrical forces act at a distance. B) Objects must be touching one another to exert electrical force. C) Air cannot conduct electricity, it is conducted only by solid materials. D) Opposite electric charges always repel one another.

A. Because electrical forces act at a distance, charged objects brought near a neutral object will cause electrons on the neutral object to rearrange their position

A(n) __________ is a closed, conducting path. A) circuit B) current C) resistor D) ampere

A. For charges to flow in a wire, it must be connected in a closed loop, or circuit.

What is the standard voltage difference of electrical energy entering homes in the United States? A) 120 V B) 220 V C) 1200 V D) 12 V

A. The standard voltage difference is 120 V.

__________ is the push that causes charges to move. A) Voltage difference B) Resistance C) Induction D) Static

A. Voltage difference is like an electrical pressure that pushes charge.

The purpose of fuses and circuit breakers is to _________. A) prevent circuits from overheating B) prevent breaks in the circuit C) decrease the resistance in a series circuit D) allow circuits to be overloaded

A. prevent circuits from overheating Both devices cause a break in the circuit and stop the flow of current which prevents the circuit from overheating.

In which type of circuit does current have only one loop to flow through? A) series B) uniform C) open D) parallel

A. series In a series circuit, the current has only one loop to flow through.

How much electrical energy is used by an appliance that draws 13 A of current at a voltage difference of 200 V for 1h? A) 2600 W B) 2.6 kWh C) 26 kWh D) 15.38 W

B. 2.6 kWh are used.

Why are metals good conductors of electricity? A) The outer energy levels of metals are nearly filled. B) Outer-level electrons are weakly held. C) Metals do not share the electrons in their outer energy levels. D) Outer-level electrons are tightly held.

B. Outer-level electrons are weakly held. Metals are good conductors because their outer-level electrons are weakly held.

___ is the tendency for a material to oppose the flow of electrons. A) Induction B) Resistance C) Transistance D) Conduction

B. Resistance With few exceptions, all materials have some electrical resistance.

law of conservation of charge

charge can be transferred from object to object but cannot be created or destroyed