Laws of Motion — Question 16

From the equation of motion,

h = ut + $\dfrac{1}{2}$ gt²

Given,

g = 9.8 m s^-2

t = 2.5 s

u = 0

Substituting the values in the formula, we get,

$\text h = (0 \times 2.5) + (\dfrac{1}{2} \times 9.8 \times 2.5^2) \\[0.5em] \text h = 0 + (4.9 \times 2.5^2) \\[0.5em] \text h = 4.9 \times (2.5)^2 \\[0.5em] \text h = 30.6\ \text m \\[0.5em]$

Hence, the height of the building is 30.6 m