Question

A speedboat increases its speed uniformly from 20.0 m/s to 30.0 m/s over a distance of 2.00 x 102 m. a)      How long does it take to travel the indicated 2.00 x 102 m? b)  How much acceleration does it experience?

Answer 1

a) Given that the speedboat increases its speed uniformly, then we can use the average speed to compute the time needed to travel a distance of 2.00x10² m.

the average speed is: (20 + 30)/2 = 25 m/s

By definition,

speed = distance/time

Substituting with speed = 25 m/s, and distance = 2.00x10² = 200 m, we get:

25 = 200/t

t = 200/25

t = 8 seconds

b) By definition,

`\begin{gathered} \text{acceleration = }\frac{\text{ final speed -initial speed }}{time} \\ \text{acceleration =}(30-20)/(8) \\ \text{acceleration =}1.25\text{ }(m)/(s) \end{gathered}`