hi
A stone is thrown off a cliff at 60 km/hr with an angle of inclination of 70°. If the cliff has a 400m drop, what vertical velocity will the stone have when it hits the ground and how long will this take? (Take g = -9.8)
Vertcal velocity. Use v^2 = u^2 + 2*a*s where v = final vertical velocity, u = initial vertical velocity = (60000/3600)*sin(70°) m/s ≈ 15.66 m/s, a = -g = -9.8 m/s^2, s = 400m
v^2 = 15.66^2 - 2*9.8*400 (m/s)^2 so v = ... you can finish this off
For the time use v = u + a*t where t is the time.