Question

What is your average velocity if you drive a distance of 113 km at a speed of 47 km/h, then the same distance at a speed of 66 km/h? Answer in units of km/h.

Answer 1

Answer:

$V_{avg}=54.90\ km/h$

Explanation:

Given that

Drive 113 km at 47 km/h and another 113 km at 66 km/h.

When distance is same then average velocity can be found by using below formula:

$V_{avg}=\dfrac{2V_1V_2}{V_1+V_2}$

Here

$V_1= 47\ km/h$

$V_2= 66\ km/h$

Now by putting the values

$V_{avg}=\dfrac{2V_1V_2}{V_1+V_2}$

$V_{avg}=\dfrac{2\times 47\times 66}{47+66}$

So

$V_{avg}=54.90\ km/h$

Answer 2

Answer:

Average velocity v = 54.90 km/h

Explanation:

We have given the distance d = 113 km

First speed = 47 km/h

Time taken to cover 113 km with speed of 47 km/h

$t=\frac{distance}{speed}=\frac{113}{47}=2.4042h$

Time taken to cover 113 km with speed of 66 km/h

$t=\frac{distance}{speed}=\frac{113}{66}=1.7121h$

So total time = 2.4042+1.7121 =4.1163 hour

Total distance = 113+113=226 km

So average velocity $v=\frac{distance}{time}=\frac{226}{4.1163}=54.90km/h$