Question

Question #7ef68

Answer 1

`h=25*5=125 " "meters"`

Explanation:

`" let x be displacement in the first second"`
`"for t=2" rarr 3x`
`"for t=3" rarr 5x`

`"total="x+3x+5x=9x`

`"thus:"`

`x,3x,5x,7x,9x`

`"total distance="x+3x+5x+7x+9x=25x`

`x=1/2*g*t^2=1/2*10*1=5" displacement for the first second "`

`h=25*5=125 " "meters"`

Answer 2

`h = 125, s_3 = 45, t_f = 5`

Explanation:

The space covered during the fall is given by
`s = h-1/2g* t^2`
after `3`[s] we have
`eq_1->h-s_3 = h-1/2 g* 3^2`
Being `t_f` the impact time we have
`eq_2->0=h-1/2g*t_f^2`
and at `t_f-1` we have
`eq_3->s_3=h-1/2g*(t_f-1)^2`
Solving `{eq_1,eq_2,eq_3}` for `h,s_3,t_f` we obtain
`h = 125, s_3 = 45, t_f = 5`