A ball, dropped vertically, falls d metres in t seconds. d is directly proportional to the square of t. The ball drops 45 metres in the first 3 seconds. How many metres does the ball drop in the next 7 seconds?
d = kt2. 45 = k x 32. 45 = k x 9 (/9). 5 = k.3+7 = 10 seconds total as we are investigating the NEXT 7 seconds. d = kt2. d = 5 x 102. d = 5 x 100d = 500m in 10 seconds. As the ball drops 45m in the first 3 seconds, and then 500m in 10 seconds, the ball drops 500-45 = 445m in the last 7 seconds.
