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a body takes t second to reach a maximum height 'h' m,when projected vertically upward from the groun.find the position of the body after t/2 seconds from the ground in terms of h.

 v=u+at……… (1).

 a=-g for a body projected vertically upward.

 v= 0 at the highest pt.

Substituting in (1),

Time of ascent,          t=u/g.

At t/2 seconds,            t= u/2g.

Substitute in               S=ut – ½ gt2

                                    = (u* u/2g) - ½ g*(u/2g) 2

                                    = (u2/2g) – (u2/8g)

                                    = 3u2/8g………. (2).

Maximum height,  h   = u2/2g [this is obtained by substituting a=-g and v= 0 in

v2-u2=2aS].

u  = root(2gh)

substitute u in (2),   S = 3*( root(2gh))2/8g

    = (3*2gh)/8g

= ¾ h.