Question

A man walks at a speed of 6 km/he for 1 km and 8 km/hrs for next 1 km.The average speed for the walk of 2 km is ___ N/7 km/h​

Answer 1

Hi,

Here is your answer

Given:

For the first part of journey

Speed=6km/hr

Distance=1km

For the second part

Speed=8km/hr

Distance=1km

To find:

Average speed for the whole journey

Solution:

Average speed is given by the equation,

Average speed=Total distance/Total time

Time taken for first part of journey

Time=Distance/Speed

Hence,

Time=1/6 hrs

Time taken for seconnd part

Time=1/8

Hence total time taken=1/6+1/8=7/24

Total distance travelled=1+1=2km

Substitute these datas in the equation for average speed

We get,

Average speed=2÷7/24

Average speed=6.86km/hr

Notes:

1. Speed is a scalar quantity. The SI unit of speed is m/s

2. The equation for calculating speed is

Speed=Distance/Time

Hope this helps you.