A car covers the first half of the distance between the two places at $$40$$ $$kmh-1$$. and another half at $$60$$ $$kmh-1$$. The average speed of the car is

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A car covers the first half of the distance between the two places at $$40$$ $$kmh-1$$. and another half at $$60$$ $$kmh-1$$. The average speed of the car is

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As from the question, Average speed of the car, vav                                         $$=$$ Total distance travelled by the body (d) Total time taken $$t1+t2$$      …(i)So$$, now time taken in $$1st$$ half of the distance,                          $$t1=$$ Time $$=$$ Distance  Velocity $$=d2$$×$$40$$⇒                    $$t1$$ $$=$$ $$d80$$                 $$($$∵ Distance $$=d2$$, velocity $$=40kmh-1$$ $$) Time taken for $$2nd$$ half, $$t2=d2$$× Velocity So,                                 $$t2=d2$$×$$60=d120$$                                                 $$($$∵ distance $$=d2$$, velocity $$=60kmh-1$$ $$)$$ Now, average velocity, $$vav=dd80+d120$$              [From Eq. (i})                                          $$=d$$×$$80$$×$$120200d=48kmh-1$$

A car covers the first half of the distance between the two places at 40 kmh-1. and another half at 60 kmh-1. The average speed of the car is

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