The centripetal acceleration of an object is given by the relation,

where Ac = centripetal acceleration =
R = radius of rotation = 15 m
V = speed of astronaut
Hence, 
solving this we get, V = 38.34 m/s
Answer:

Explanation:
When teacher falls into the cliff then she shout for Help at the same time
so here we know that sound will go down and reflect back up
so here in 3 s distance traveled by the sound



now in the same time the distance that teacher will fall down is given as



now total distance traveled by teacher and sound in 3 s


this total distance must be equal to twice the height of the cliff


An initial velocity is:
v o = 25 m/s
The vertical component of the initial velocity:
v o y = v o * sin 60° =
= v o * √3 / 2 = 25 m/s * √3 / 2 = 21.65 m/s
Answer:
The approximate vertical component of the initial velocity is 21.65 m/s.