Uncertainty in Physics

1. Explain the difference between absolute uncertainty and percentage uncertainty. Give an example of when it might be more useful to use percentage uncertainty.

2. A rectangle's length is measured to be 5.0 ± 0.1 cm and its width is 3.0 ± 0.1 cm. Calculate the area of the rectangle and the uncertainty in the area.

3. A student measures the voltage across a resistor to be 12.0 ± 0.5 V and the current through it to be 2.0 ± 0.1 A. Calculate the resistance using Ohm's Law (R = V/I) and determine the uncertainty in the calculated resistance.