Practical 6 - Investigation of the I-v characteristic of a filment of a lamp and a metal wire at constant temperature

Question 1

What is potential difference proportional to?

Answer 1

Current
(I and V)

Question 2

How can we determine the validity of Ohm’s law in this practical?

Answer 2

Plotting the I-V characteristic of both a metal wire and a filament lamp

Question 3

What are the two components we’re using in this practical?

Answer 3

Filament bulb and metal wire

Question 4

What would the I v.s V graph be for a metal wire?

Answer 4

Linear

Question 5

What would the I v.s V graph be for a filament of a lamp?

Answer 5

Non-linear

Question 6

Draw and label the circuit required for this practical

Answer 6

(See notes)

Question 7

How do we control the voltage in this practical?

Answer 7

Variable d.c voltage supply

Question 8

What’s the voltage and wattage of the filament bulb used?

Answer 8

12V, 24W

Question 9

What type and of what length metal wire do we use?

Answer 9

1m constantan on a wooden batten

Question 10

What’s the experimental method for this practical?

Answer 10

-slowly increase the voltage output from the variable d.c. voltage supply’s minimum value
-record current through and the potential difference across the component for a range of values
-graph of I v.s V for both the bulb and wire’s values