Question

find the total displacement of a body in 8 s starting from rest with an acceleration of 20cm/s2

Answer 1

find the total displacement of a body in 8 s starting from rest with an acceleration of $20\mathrm{cm/s^2}$

Displacement in uniformly accelerated motion equals:

$$s = u t + \frac{a t^2}{2}$$

s = displacement

u = initial velocity

a = uniform acceleration

t = time

In our case body was starting from rest, therefore $u = 0$:

$$s = \frac{a t^2}{2} = 20 \frac{\mathrm{cm} \cdot (8 \cdot s)^2}{2} = 640 \mathrm{cm} = 6.4 \mathrm{m}$$

Answer: 6.4 m