03- Electricity

Question 1

3. Explain how the potential along a wire varies with distance from A when the switch is closed.

Answer 1

V=IR
Current is the same throughout the wire
Resistance increases over a larger distance as more electron are involved
Resistance increases , Potential Difference also increases
so PD is proportional to length of wire

Question 2

3. Statement

Data demonstrates that the filament lamp obeys Ohm’s law because the graph is linear

Assess validity

y-intercept around 0.4
weak positive correlation

Answer 2

Ohm’s law requires current to be directly proportional to PD
The line should pass through the origin
There is scatter around the line of best fit so the line might actually be a curve
Graph doesnt meet the conditions for ohm’s law
students statement invalid

Question 3

3. Describe how the current through this diode varies for positive and negative PDs

Threshold voltage = 0.7

Answer 3

The diode only conduct current when the PD is at least +0.7V

The diode doesn’t conduct current when the PD is negative

Question 4

3.