Question

A person compelete half of his journey with speed v1 and rest half with spaad v2 the average speed of the person is

Answer 1

Let the distance be 2d
Let the time be t.
Case1:
Speed=v¹
Time=t¹=distance/speed¹
T¹=d/v¹
Case2:
Speed=v²
Time=t²=distance/speed²
T²=d/v²
Now,
Total distance=2d
Total time=t¹+t²=d/v¹+d/v²=(dv²+dv¹)/v¹v²
Now,
Average Speed=total distance/total time
=2d/(dv¹+dv²)/v¹v²
=2d×v¹v²/(dv¹+dv²)
(ÆÑẞWĒR)