An engineering team tests the reaction time of an emergency safety-shutoff mechanism using a calibrated vertical drop-bar. In a series of trials, the mean distance the drop-bar fell before the brake fully engaged was 18.5 cm.
Calculate the average reaction time of the shutoff mechanism. Give your answer to 2 significant figures.
Use the equation:
time2=distance490 \text{time}^2 = \frac{\text{distance}}{490} time2=490distance39 exam-style questions on Edexcel GCSE Physics 2.5 Stopping and braking distances. Each one has a worked solution and a mark scheme showing where the marks go.