Question

a bus travels a distance of 120 km with a speed of 40 km/h and returns with a speed of 30km/hr . calculate the average velocity of the entire journey.

Answer 1

Hi Dear !!

Here is Your Answer.

Given :
A bus travels a distance of 120 km with a speed of 40 km/h and returns with a speed of 30 km/h.

We know that average speed$=\frac{total \: distance \: travelled}{total \: time \: taken}$
Total Distance = 120 + 120 = 240 km. (Bcoz it travelled the same distance two times)

Now, time taken, t1 = S/v = 120/40
= 3 hrs.

Time taken while returning = 120/30
= 4 hrs.

Total time taken = 3+4 = 7 hrs.

Now, Average Speed =
$= \frac{240}{7} = 34.28 \: km \: {h}^{ - 1}$
Hence, the average speed during the entire journey is 34.28 km/h.

Hope You Got It