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A pirate 50.0 m away from a tall ship wants to shoot the crow’s nest off this ship. She angles her cannon at 250 and fires; her cannonball leaving at only 68 m/s. Somehow, the lass pegs the crow’s nest. How high was the crow’s nest?

Respuesta :

MathPhys

Answer:

20.1 m

Explanation:

First, find the time it takes for the cannonball to travel the horizontal distance of 50.0 m.

Given (in the x direction):

Δx = 50.0 m

v₀ = 68 cos 25° m/s

a = 0 m/s²

Find: t

Δx = v₀ t + ½ at²

(50.0 m) = (68 cos 25° m/s) t + ½ (0 m/s²) t²

t = 0.811 s

Now find the vertical displacement after that time.

Given (in the y direction):

v₀ = 68 sin 25° m/s

a = -9.8 m/s²

t = 0.811 s

Find: Δy

Δy = v₀ t + ½ at²

Δy = (68 sin 25°) (0.811 s) + ½ (-9.8 m/s²) (0.811 s)²

Δy = 20.1 m