Ohms Law And Resistance Chapter8

Question 1

What is the purpose of a battery?

Answer 1

The purpose of a battery is it is the source of potential energy in a circuit.

Question 2

In a battery, what form of energy is converted

into electric potential energy?

Answer 2

Chemical energy is transformed into electric potential energy.

Question 3

What is the relationship of electric potential
energy, charge, and potential difference
(voltage)?

Answer 3

The amount of electric potential energy is dependent on the amount of charge separated (coloumbs) and the electric potential difference (voltage)

Question 4

What materials are needed to produce an

electrochemical cell?

Answer 4

Two different metals and an electrolyte.

Question 5

List five methods of producing electric energy.

Answer 5

Friction, photoelectrochemical cells, thermocouples, generators and piezoelectric crystals.

Question 6

What unit is used for measuring voltage?

Answer 6

Volts

Question 7

What is the purpose of a voltmeter?

Answer 7

To measure voltage

Question 8

What is the purpose of an ammeter?

Answer 8

To measure current

Question 9

What is the relationship between amperes

(A) and milliamperes (mA)?

Answer 9

100mA = 1A

Question 10

What is the difference between conventional

current and electron flow?

Answer 10

Electron flow is when extra electrons accumulate on one electrode of an electrochemical cell making it negatively charged, and the loss of electrons on the other electrode becomes positively charged. The electrons would then flow continuously through the circuit to from the negative terminal until they reached the positive terminal. Conventional current is the exact opposite, when charge flows from the positive electrode of an electrochemical cell to the negative electrode.

Question 11

What are the four basic components of an electric circuit?

Answer 11

Source of electricity, conductor ; wire that is a pathway for electrons, load which turns electrical energy into other forms of energy, and a switch which can stop and start the flow of electrons.

Question 12

Explain the relationship between resistance and resistor.

Answer 12

Resistance is the property of a material that has the ability to slow down current and change it into other forms of energy. A resistor is anything with that property.

Question 13

State the relationship of voltage (V), current

I), and resistance (R

Answer 13

V = IR
I = V/R
R = V/I

Question 14

When an electron passes through a resistor,

what happens to its electric energy?

Answer 14

It is transformed into other forms of energy.

Question 15

Resistors have a maximum of four coloured bands stamped on their surface. What does each band represent?

Answer 15

First digit, second digit, multiplier, accuracy.