Activity 8.6 Class 9 Science Chapter 8 Motion
Activity 8.6 asks us to calculate the time; that we take while going to bus-stop or school; and calculate the distance if our speed is 4km/hr.
Speed is the distance traveled in a unit time. Here it is given in km/hr, so we need to calculate walking time in an hour. For example if it takes 12 minutes to reach school then time in the hour will be 12/60 =0.20 hr.
Now, Distance= speed x time
so, distance= 4 km/hr x 0.20 hr
=0.8 km or 800 meter.
We can also convert km/hr speed to meter/minute or meter/minute. In all the case answers will be the same. The precaution to take is that time should also be in the same unit. Here, for a shorter distance or small walk time we should prefer meter/minute and minute.
***Activity 8.6 Class 9 Science Chapter 8 Motion***
Ref: NCERT Class 9 Science Chapter 8.