Question

In 20 minutes, kara ran 2.40 km on a treadmill facing due east. relative to the gym, what were her displacement and average velocity during this time interval?

Answer 1

Relative to the gym they are both zero since she is on a treadmill. Relative to the belt of the treadmill she was moving but not relative to the gym.

Answer 2

Answer:

Displacement is zero.

Average velocity 7,2 km/hr

Explanation:

In order to calculate the average velocity we just ahve to do a simple rule of three, where 20 minutes is divided by 2,4 kilometers, so how much would she advance in 60 minutes?:

$\frac{20}{2,4} =\frac{60}{x}\\ x=\frac{60*2,4}{20}\\ x= 7,2 km/hr$

So her average veocity will be 7.2 km/hr

And her displacement will be zero because she was on a treadmill so her location didn´t change at all.