Question

a body covers half of the distance with speed u and other half speed v then find average speed of body

Answer 1

the answer is  "u+v/ total time taken" because average speed is total distance by total time taken.
 

Answer 2

Answer:

Total distance covered by body=

$d = \frac{s}{t}= \frac{2uv}{u + v}$

Explanation:

Let the total distance be 's'

Body covers the distance S/2 with speed 'u'

time taken by the body to cover this distance would be

$time \: t = \frac{distane}{speed}$

$t {1} = \frac{ \frac{s}{2} }{u}$

$t 1= \frac{s}{2u} - - - 1$

Body covers rest of the distance S/2 with speed 'v'

$t {2} = \frac{ \frac{s}{2} }{v}$

$t2 = \frac{s}{2v}$

total time taken by the body =

$t = t1 + t2$

$t = \frac{s}{2u} + \frac{s}{2v}$

$t = s( \frac{1}{ 2u} + \frac{1}{2v} )$

$t = s( \frac{u + v}{2uv} )$

$d = \frac{s}{t}= \frac{2uv}{u + v}$

total distance covered by body=

$d = \frac{s}{t}= \frac{2uv}{u + v}$

#SPJ3