Answer:
[tex]s=274.2857\ m[/tex] is the distance from the target before which the pilot must release the canister.
Explanation:
Given:
Time taken by the canister to hit the ground:
using equation of motion
[tex]h=u_y.t+\frac{1}{2} g.t^2[/tex]
where:
[tex]u_y=[/tex] initial vertical velocity of the canister = 0 (since the the object is dropped from a horizontally moving plane)
[tex]t=[/tex] time taken to hit the ground
[tex]90=0+0.5\times 9.8\times t^2[/tex]
[tex]t=4.2857\ s[/tex]
Now the horizontal distance travelled by the canister after dropping:
[tex]s=v_x\times t[/tex]
[tex]s=64\times 4.2857[/tex]
[tex]s=274.2857\ m[/tex] is the distance from the target before which the pilot must release the canister.