A ball, dropped vertically, falls d metres in t seconds. d is proportional to the square of t. The ball drops 45 metres in the first 3 seconds. How far does the ball drop in the next 7 seconds?

First we form equations from the information given in the question. The first equation we can form is that d is directly proportional to the square of t. This means that d = kt2 ,where k is a constant of proportionality. Using the given relationship of d = 45 when t = 3, we can work out the constant k. 45 = k3245 = 9kk = 5The relationship between d and t is now d = 5t2 We are asked for the next 7 seconds, so we cannot simply substitute t = 7 into this equations. If we did this then we would be working out the first 7 seconds.Instead we do 3 + 7 = 10 to work out the total time.We will work out the distance dropped in 10 seconds and then subtract the first 3 seconds worth of distance. When t = 10, d = 5102 = 500Then we subtract the first 3 seconds worth of distance, 500 - 45 = 455455 is the distance travelled by the ball in the next 7 seconds.

Related Maths GCSE answers

All answers ▸

Karen got 32 out of 80 in a maths test. She got 38% in an English test. Karen wants to know if she got a higher percentage in maths or in English. Did Karen get a higher percentage in maths or in English?


Find the highest common factor (HCF) of 12 and 18.


How to find the exact formula of the function if the graph of it is given?


two connected triangles in an overall shape ABCD, find length AD


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2024

Terms & Conditions|Privacy Policy
Cookie Preferences