Practical - I V Graphs

Question 1

What is the purpose of the required practical?

Answer 1

To apply skills and knowledge to practicals and answer questions on them.

Question 2

What is the relationship you need to determine for a lamp, resistor, and diode?

Answer 2

The relationship between current and potential difference (p.d.).

Question 3

What must you be able to do with I-V graphs?

Answer 3

Draw and interpret I-V graphs and understand the shape characteristic of the component.

Question 4

What is the significance of the gradient of the I-V graph?

Answer 4

The gradient is not related to the resistance, but resistance can be calculated from p.d. and current values.

Question 5

What component needs to be connected with a protective resistor?

Answer 5

The diode.

Question 6

What is the role of a variable power supply or resistor in the experiment?

Answer 6

To change the current in both directions.

Question 7

Fill in the blank: The p.d. in V should be plotted against the ______ in A.

Answer 7

current

Question 8

What happens to resistance as p.d. increases for the lamp?

Answer 8

Resistance increases.

Question 9

What is the name of component X if the graph is symmetrical?

Answer 9

X is a lamp.

Question 10

What changes need to be made to repeat the experiment with a diode?

Answer 10

1. Use a diode instead of a lamp
2. Connect with a protective resistor.

Question 11

Sketch the I-V graph for a diode and explain its shape in terms of resistance.

Answer 11

The I-V graph for a diode shows a non-linear relationship; resistance changes with current.