WAEC Physics 2017 Paper

Concept:Complementary variables are pairs of physical quantities that cannot both be measured exactly at the same time.Explanation:Heisenberg's uncertainty principle deals with such complementary pairs.The most important pair is position and momentum.Their uncertainty relation is given by:$$\Delta x \cdot \Delta p \ge \frac{\hbar}{2}$$Here, $\Delta x$ is the uncertainty in position and $\Delta p$ is the uncertainty in momentum.Among the given options, position and momentum form the correct complementary pair.Answer:C. Position and momentum