(5.1) - Current Electricity

Question 1

What is Current?

Answer 1

• The rate of flow of charge

Question 2

What is Voltage / Potential Difference

Answer 2

Potential difference as work done per unit charge

Question 3

What is Ohm’s Law?

Answer 3

I ∝ V, but only if other physical conditions remain constant

Question 4

Describe energy transfers that happen in a simple circuit with a light bulb and a battery

Answer 4

1. Energy is stored in battery as chemical
2. Chemical -> Kinetic to electrons
3. Electrons collide with fixed positive ions in the wire, Ions store it as Kinetic, causing them to vibrate more, and transfers to surrounding as heat
4. Electrons collide with ions in filament, transfers energy to filament. Bulb transfers energy to surroundings via light and dissipates as heat.

Question 5

How many electrons in 1 Coulomb

Answer 5

1 / 1.6 * 10 ^ -19 = 6.25 * 10 ^ 18

Question 6

I = Q / t. Explain how to calulate Q without rearrganging equation (total charge) (use external equations)

Answer 6

Q = number of electrons * charge of electron

Question 7

What is Conventional Current?

Answer 7

Flow of positive charge (positive to negative)

Question 8

What is Electron Flow?

Answer 8

Flow of negative charge (negative to positive)

Question 9

Why is copper used for wires?

Answer 9

Low resistance