Mark Ji shoots a 40gram arrow straight up in the air at 30m/s during a home archery training session

a. assuming no air resistance, what is the maximum height that the arrow could reach?

b. How fast is the arrow going when it hits the ceilings at a height of 15.0m?

a.

Equate energies:
mgH = (1/2)mv0²
v0=30 m/s
g=9.8 m/s²
Solve for H.

b.
Equate energies:
mg(15) = (1/2)m(v0^sup2;-v²)
solve for v.