Question

a car travels a distance x km with a speed 36 km/hr and next xkm/hr with a speed of 45km/hr .The average speed of the car is

Answer 1

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Given :

A car travells a distance x km with a speed 36 km/hr and next x km with a speed of 45 km/hr

To Find :

Average speed of car...

Formula :

when a body covers half a distance with speed v1 and another half a didtance with speefmd v2 then average velocity is given by...

$\: \: \: \: \: \: \: \: \: \: \: \: \boxed{ \rm{ \pink{v{ \tiny{av}} = \frac{2v1v2}{v1 + v2} }}}$

Calculation :

$\rm \: v_{av} \: = \frac{2 \times 36 \times 45}{36 + 45} \\ \\ \therefore \rm \: v_{av} = \frac{3240}{81} \\ \\ \boxed{ \red{ \rm{v_{av} = 40 \: \frac{km}{hr} }}}$