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A carpenter tosses a shingle off a 9.4 m high roof, giving it an initial horizontal

velocity of 7.2 m/s.

User Laxmikant
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1 Answer

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Sounds like the shingle/ball is thrown from the roof horizontally, so that the distance it travels × after time t horizontally is
X = (7.2 m/s) t
The object's height y at time t is
y= 9.4 m -1/2 gt^2?
where g = 9.80 m/s?
is the magnitude of the acceleration due to gravity, and its vertical velocity is V =-gt

(a) The object hits the ground when y = 0:
0 = 9.4 m - 1/2 gt^2
+2 = 2 * (9.4 m) / (9.80 m/s?)
t=1.92 s at which time the object's vertical velocity is
V =-g (1.92 s) = -18.8 m/s = -19 m/s

(b) See part (a); it takes the object about 1.9 s to reach the ground.

(c) The object travels a horizontal distance of x = (7.2 m/s) * (1.92 s) = 13.8 m = 14 m
User CheapSteaks
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