Physical Science-Unit 9 Test

In the following diagram, the voltage is 1.5 volts and the resistance is 7.5 ohms. Use Ohm's law to determine the current in the circuit.

**Incorrect** 6.0 amps

Which of the following shows resistors in a parallel circuit?

**Incorrect** B

Ocean water conducts electrical current because it contains _____.

**Incorrect** isotopes

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

**Incorrect** opens

Select all that apply. Which of the following statements are true? Positively charged objects attract other positively charged objects. Negatively charged objects attract other negatively charged objects. Positively charged objects attract negatively charged objects. Negatively charged objects attract neutral objects. Positively charged objects attract neutral objects.

**Partial Credit** C and D

If the strength of the magnetic field at A is 200 units and the strength of the magnetic field at B is 50 units, what is the distance to B?

10 units

A 500-watt vacuum cleaner is plugged into a 120-volt outlet and used for 30 minutes. How much current runs through the vacuum?

4.2 amps

If the strength of the magnetic field at B is 20 units, the strength of the magnetic field at A is _____.

80 units

Which of the following factors influence the electrical resistance of a circuit?

A, B, and D

In which of the following circumstances would a current register on the galvanometer?

B and C

As more resistors are added to a parallel circuit, the current

Increases

Why is current supplied to consumers from generating plants in the form of alternating current?

It is a much more efficient mode of transmitting electricity than direct current.

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

Van de Graaff generator

The element in an incandescent light bulb that releases light energy is _____.

a thin tungsten filament

The Greeks studied charges using _____.

amber

Ampere showed that parallel wires carrying current in the same direction would____each other.

attract

A positively charged atom or group of atoms can be called a(n) _____.

cation

The electricity that is delivered to our homes from regional generating stations moves over transmission lines that are _____.

high voltage and low current

The unit of resistance is _____.

ohms

In a circuit, a battery is used to _____.

raise the potential of electrons

Charge q is 1 unit of distance away from the source charge S. Charge p is four times further away. The force exerted between S and q is _____ the force exerted between S and p.

sixteen times

Electrostatic charges are created by _____.

stripping outer electrons from substances

The unit of electric potential or electromotive force is the _____.

volt