Question

A typical maximum speed for a unicycle is about 5 mph. While riding his giraffe unicycle, Mike accelerates from rest to the typical maximum speed in 2.5 s. How far does Mike travel during this time?

Answer 1

Answer:

$s = 9.167\,ft$

Explanation:

Converting units into fundamental units is the first step. The maximum speed is:

$v_{f} = (5\,\frac{mi}{h} )\cdot (\frac{5280\,ft}{1\,mi} )\cdot (\frac{1\,h}{3600\,s} )$

$v_{f} = 7.333\,\frac{ft}{s}$

Let assume that Mike accelerates at a constant rate. Hence, accelaration is obtained from this formula:

$a = \frac{v_{f}}{t}$

$a = \frac{7.333\,\frac{ft}{s} }{2.5\,s}$

$a = 2.933\,\frac{m}{s^{2}}$

Then, distance travelled by the unicycle can be found easily:

$s = \frac{(7.333\,\frac{m}{s} )^{2}}{2\cdot (2.933\,\frac{m}{s^{2}} )}$

$s = 9.167\,ft$