Question

Projectile motion: If a player hits a voley ball 2.35 m from the ground and gives it an initial velocity of Vo= 14 m/s forward and 3.5 m/s upwards.
a) Ignoring air resistance show whether the ball clears the net or not.
b) Similarly, show whether the ball lands inbound on the other side of the court or not.

Answer 1

the height is
y = 2.35 + 3.5t - 4.9t^2
The horizontal distance is x = 14t

without knowing the height of the net, or the length of the court, there is no way to answer the questions.

Answer 2

a. Vo = 14+3.5i = 14.4 m/s.[14o].
Y^2 = Yo^2+2g*h = 0
3.5^2+(-19.6)h = 0
h = 0.625 m. above launching point.
2.35+0.625 = 3 m. above gnd.
The net is app. 2.4 m above gnd.
Range = Vo^2*sin(2A)/g = 14.4^2*sin(28)/9.8 = 9.9 m. = hor. distance.
Therefore, the ball clears the net.

b. 9.9m * 3.3Ft./m = 32.7 Ft.
Distance from net to out-of-bounds line = 30 Ft.
Therefore, the ball does not land inbound.