Question

A body starting with initial velocity u moves with a constant accelearation a. Find the expression for distance travelled in n^th second. A body was dropped from a very high building, calculate its distance travelled in 5th second. [5 MARKS]

Answer 1

Part 1 : 2.5 Marks
Part 2 : 2.5 Marks
$S_n=Distancetravelledintseconds-Distancetravelledin(t-1)seconds$
$=[ut+\frac{a{t}^2}{2}]-\left[u\right(t-1)+\frac{a{(t-1)}^2}{2}]$
$=u+\frac{a(2n-1)}{2}$
$=u+a(n-\frac{1}{2})$

$S_5=0+10(5-\frac{1}{2})$
$=45m$