Question

A bicycle rider increases his speed from 5 m/s to 15 m/s in 10 seconds

Answer 1

To find the acceleration of the bicycle rider, we are going to use the acceleration formula: $a= \frac{v_{f}-v_{i}}{t}$
where
$a$ is the acceleration 
$v_{i}$ is the initial speed 
$v_{f}$ is the final speed 
$t$ is the time 

We know from our problem that increases his speed from 5 m/s to 15 m/s in 10 seconds, so his initial speed is 5 m/s and his final speed is 15 m/s; therefore, $v_{i}=5$, $v_{f}=15$, and$t=10$. Lets replace those values in our formula:
$a= \frac{v_{f}-v_{i}}{t}$
$a= \frac{15-5}{10}$
$a= \frac{10}{10}$
$a=1$

We can conclude that the acceleration of the bicycle rider 1 m/s^2