Answer :
Answer:
81.6 m
Explanation:
Answer: 81.6 m.
The time it takes gravity to slow 40 m/s to zero when it teaches maximum height is
-v(initial) / -g = t
-40 m/s / -9.8 m/s^2 = 4.08 s
The height reached is the average velocity times this time 4.08 s, with v(avg) = [v(initial) + v(final)] / 2 with v(final) = 0. v(avg) = v(initial) / 2 = 40 m/s / 2 = 20 m/s.
So the distance d of maximum height is
d = v(avg)•t
d = 20 m/s • 4.08 s = 81.6 m.
Answer:
80m
Explanation:
time taken for stone to reach max-height is t=final velocity - intial velocity / acceleration due to gravity
t=v-u/g
where:
v=0 , u=40m/s ,g=-10m/so
: t=0-40/-10
t=4secs
: max-height reach=ut + 0.5gt²
=(40)(4)+(0.5)(-10)(4)I
=160-5(16)
=160-80
=80m