Electrical - Voltage

Question 1

Potential difference will exist between two points in a circuit that have a…?

Answer 1

Difference in charge

Question 2

What is potential difference measured in?

Answer 2

Volts

Question 3

What is the name of the force which drives the current through a circuit?

Answer 3

Electromotive force

Question 4

Name 6 methods by which voltage can be produced

Answer 4

1. Chemical
2. Friction
3. Induction
4. Pressure
5. Heat
6. Light

Question 5

To produce a voltage chemically, the two metal plates should be made from…?

Answer 5

Two dissimilar metals

Question 6

Give an example of where voltage is produced by friction.

Answer 6

Rub a balloon on hair and stick it to a wall

Question 7

Name the 3 requirements needed to produce a voltage by induction

Answer 7

1. An Electrical conductor
2. A magnetic field
3. Relative movement

Question 8

What determines the polarity of an induced voltage?

Answer 8

The direction of movement between metallic field and conductor

Question 9

What determines the amount of voltage produced by a thermocouple?

Answer 9

1. The two types of materials used
2. The difference in temperature

Question 10

What is the name given to the materials in a solar panel?

Answer 10

Semiconductor

Question 11

Give an example where voltage is produced by pressure.

Answer 11

Piezo crystal

Question 12

Sketch and label a conductor, showing current flow:

Answer 12

clue:
free electrons, bound electrons, wire, atom, direction of current flow

Question 13

Sketch and label a simple, wet cell:

Answer 13

clue:
positive electrode, negative electrode, filament, container, electrolyte, direction of electron flow

Question 14

Ohm’s Law states that…

Answer 14

a Current flowing through a conductor is directly proportional to the voltage applied across it, providing the temperature stays constant, and is inversely proportional to the resistance.