The distance(s) in metres covered by a particle in motion at any time, t seconds, is given by S =120t – 16t\(^2\). Find in metres, the distance covered by the body before coming to rest.
- 220
- 222
- 223
-
225
The correct answer is: D
Explanation
s = 120t - 16t\(^2\) - 16t\(^2\)
\(\frac{ds}{dt} = 120 - 32t\)
120 - 32t = 0
\(\frac{32t}{32}\) = \(\frac{120}{32}\)
t = 3.75
s = 120(3.75) - 16(3.75)\(^2\)
= 450 - 225
= 225