Ohms Law

At a constant temperature, the electrical current flowing through a fixed linear resistance is directly proportional to the voltage applied across it, and also inversely proportional to the resistance.

"The electrical current flowing through a fixed linear resistance is directly proportional to the voltage applied across it" means that as the voltage increase by a certain percentage so will the current.

"inversely proportional to the resistance" means that as the resistance increases the current will decrease..

Tasks

The following steps should be carried out and notes taken on what you notice.

1. Without using the simulator pick a resistance between 1 and 50Ω and voltage between 1 and 240V.
2. Calculate the current using Ohms Law triangle and covering over the bottom left corner to reveal that you need to divide the voltage by the resstance.
3. Check your calculation by moving the sliders. Note some answers may be out a little due to the simulator rounding to 2dp.

Tasks

Note how

1. As the voltage increases the current increases.
2. As the resistance increases the current & angle of the slope of the line decreases.

For those who remember y = mx+c from school the slope equation section in black is of this format except it has an unwritten c value of 0 as the current always needs to reach aero when the voltage does.