Question

2. For one hour, you travel east in your car covering 100 km .Then travel south 100 km in 2 hours. You would tell your friends that your average velocity was
47 km/hr
67 km/hr
75 km/hr
141 km/hr
200 km/hr
Answer is 47 Km /h explain why ?

Answer 1

Answer:

Explanation:

Average velocity is change in position over the change in time. You have to take the directions into account. 100km east and then 100km south. That forms a right triangle, so you can use Pythagorean's theorem to find the hypotenuse which would be the displacement from his initial position:

$\sqrt{100^2+100^2} = \sqrt{20,000}=141.42km$

Now take the displacement and divide it by the time it took to do the trip, 3 hours:

$141.42km/3hours=47.14km/h$