When a ruler falls vertically, 5 different persons catch it with different reaction times. (g = 9.8 m s^ -2 ) A. Person A has reaction time of 0.20 s. B. Person B has reaction time of 0.22 s. C. Person C has reaction time of 0.18 s. D. Person D has reaction time of 0.19 s. E. Person E has reaction time of 0.21 s. What is the correct order of the distance travelled by the ruler for each person ?
C. B > E > A > D > C
The distance travelled by the ruler falling freely under gravity is given by d = 1 2 g t^2. Since g is constant, the distance d is directly proportional to the square of the reaction time t. Thus, a larger reaction time results in a greater distance travelled by the ruler. The given reaction times are: t_A = 0.20 s t_B = 0.22 s t_C = 0.18 s t_D = 0.19 s t_E = 0.21 s Arranging the reaction times in descending order: 0.22 > 0.21 > 0.20 > 0.19 > 0.18 This corresponds to: t_B > t_E > t_A > t_D > t_C Therefore, the correct order of the distance travelled by the ruler is: B > E > A > D > C Answer: B > E > A > D > C
Related: Physics — Motion In One Dimension · All PYQ Banks