Question

 A car travels from stop A to stop B with a speed of 30 km/h and then returns back to A with a speed of 50 km/h. Find

       (i)  displacement of the car.

       (ii)  distance travelled by the car.

       (iii)  average speed of the car.

Answer 1

Your answer is --

Given, S1 = 30km/h and S2 = 50km/h


(i) Since, car return back to its initial position .

So, displacement will be zero (0).


(ii) Let , the distance travels by car from A to B be x km

The car travel from A to B and return back to A

So, total distance = 2x km

(iii)

time interval of car from A to B t1= x/S1

= (x/30)hour

time interval of car from B to A t2 = x/S2

= (x/50)hour

Therefore , average speed

= total distance / total time

= 2x/t1+t2

= 2x/(x/30+×/50)

= 2x(5x+3x/150)

= 2x/8x/150

= 150/4

= 37.5 km

【 Hope it helps you 】