4.2.2 Resistance and Ohm's Law

How does the cross sectional area of the wire affect resistance?

Resistance is inversely proportional to the cross sectional area of the wire. So as the cross sectional area increases the resistance decreases.

Define resistance:

Resistance is the potential difference per unit current.

How does the temperature affect the resistance of a thermistor?

Resistance will decrease as the temperature increases.

How does the temperature affect resistance?

Resistance will increase as temperature increases due to the extra energy and collisions caused by this rise in temperature.

State Ohm's law:

The current through a conductor is directly proportional to the potential difference across it, providing that physical conditions remain constant.

How does the material affect resistance?

If the material is a conductor it will have less resistance due to free moving electrons.

How does the length of wire affect resistance?

Resistance is directly proportional to the length of the wire. So as the length of wire increases as does the resistance.