[tex]d = u \times t \: + \frac{1}{2} \times a \times {t}^{2} [/tex]
Since initial velocity is zero hence , u = 0
=> d = 1/2 * a * t2
[tex]d = 0.5 \times 9.8 \times {4.2}^{2} [/tex]
on solving we get
d = 86.436 metres
Note ; Here Gravitational Acceleration is take as , g = 9.8 m/s2
