Question

A particle travels first half of the total distance with constant speed `v_1` and second half with constant speed `v_2.` Find the average speed during the complete journey.

Answer 1

Correct Answer - A::B

`t_1=d/v_1 and t_2=d/v_2`
Average speed =`("total distance")/("total time ") = (d+d)/(t_1+t_2)=(2d)/((d//v_1)+(d//v_2))=(2v_1v_2)/(v_1+v_2)`