Trusted since 2008
LoginRegister
Study resources on Kenyaplex

Get ready-made curriculum aligned revision materials

Exam papers, notes, holiday assignments and topical questions – all aligned to the Kenyan curriculum.

Browse exam papers
Or go directly to:
Class notes Holiday assignments Topical questions Other resources

Describe an experiment that can be used to investigate Ohm’s law:

Describe an experiment that can be used to investigate Ohm’s law:

Answers

sharon
42420191127.png
- Close the switch and adjust the current flowing through the conductor T using the rheostat to the least possible value. Record the corresponding voltmeter reading.
- Increase the current in steps recording the corresponding voltmeter readings. Record your values in the table below:
42420191128.png
- Plot a graph of voltage against current. Hence determine the slope of the graph.
A graph of voltage against current is a straight line through the origin. Hence voltage drop across the conductor is directly proportional to the current through it;
42420191130.png
V/I = constant
The constant is known as resistance R of the conductor T under investigation.
Thus, V/I= R
Or V= IR.
Hence the slope of a voltage—current graph is equal to the resistance R of the conductor T. electrical resistance can be defined as the opposition offered by a conductor to the flow of electric current. It is measured using an ohmmeter.
The SI Unit of electrical resistance is the ohm (O). Other units include kilo-ohm (kO) and mega-ohm (MO);
1O= 2-3kO
1O= 2-6MO
Materials which obey Ohm’s law are said to be ohmic materials while those which do not obey the law are said to be non-ohmic materials. The graph of voltage against current for non-ohmic materials is a curve or may be a straight line but does not pass through the origin.
The inverse on resistance is called conductance;
Conductance= 1/ resistance R.
sharon kalunda answered the question on April 24, 2019 at 08:33

Answer Attachments

Next: Explain the benefits of ICT to a small business enterprise.

Previous: Describe an experiment to determine the specific heat capacity by the method of mixtures.

View more Physics Questions and Answers  |  Return to Questions Index

Exams With Marking Schemes

Related Questions