Question

Suppose you increase your walking speed from 5m/s to 15m/s in a period of 1 s. What is your acceleration?

Answer 1

Acceleration=change in velocity divided by change in time or $a=\frac{\Delta v}{\Delta t}$

we are given that it goes from 5m/s to 15m/s
$\Delta v=v_f-v_0$
in this case, $\Delta v=15\frac{m}{s}-5\frac{m}{s}=10\frac{m}{s}$

and the change in time or $\Delta t$ is 1 second because this change occurs over a period of 1 second

so the acceleration is $a=\frac{10\frac{m}{s}}{1s}=10\frac{m}{s^2}$
the acceleration is $10\frac{m}{s^2}$