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IronManTable
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Homework Statement
A sea bird catches a fish and then flies in an easterly direction with a speed v=7.39 m/s, h = 4.69 m above the surface of the sea. The fish has a mass of 115.3 g and is still alive. It thrashes and wiggles and as a result the bird drops the fish.
i) What is the speed of the fish when the bird drops it?
ii) What is the speed of the fish when it hits the water?
iii) When the fish hits the water it is momentarily stunned. It comes to a rest in 0.111 s. What is the magnitude of the force experienced by the fish as it comes to rest?
iv) How far horizontally from where it was dropped does the fish hit the water?
Homework Equations
v2 = u2 +2gh
v22 = v12 + 2ad
s = ut + 0.5 x t2
F = ma
The Attempt at a Solution
i) What is the speed of the fish when the bird drops it?
Since v1 = 0
v22 = v12 + 2ad
v2 = √(2ad)
v2 = √(2 x 9.8 x 4.69)
v2 = 9.59 m/s
ii) What is the speed of the fish when it hits the water?
Using Pythagoras' Theorem,
a2 + b2 = c2
∴ c = √(7.392 + 9.592)
c = 12.1 m/s
iii) When the fish hits the water it is momentarily stunned. It comes to a rest in 0.111 s. What is the magnitude of the force experienced by the fish as it comes to rest?
s = ut + 0.5 x t2
4.69 = 0 + 0.5 x a x 0.1112
a = 4.69 / (0.5 x 0.1112)
a = 761.3 m/s2
F = ma
F = 0.1153 x 761.3
F = 87.8 N
iv) How far horizontally from where it was dropped does the fish hit the water?
I can't seem to figure out a way to get this answer. Can someone please check if my answers are right and can give me an insight on how to answer this last question? Thank you!
Since v1 = 0
v22 = v12 + 2ad
v2 = √(2ad)
v2 = √(2 x 9.8 x 4.69)
v2 = 9.59 m/s
ii) What is the speed of the fish when it hits the water?
Using Pythagoras' Theorem,
a2 + b2 = c2
∴ c = √(7.392 + 9.592)
c = 12.1 m/s
iii) When the fish hits the water it is momentarily stunned. It comes to a rest in 0.111 s. What is the magnitude of the force experienced by the fish as it comes to rest?
s = ut + 0.5 x t2
4.69 = 0 + 0.5 x a x 0.1112
a = 4.69 / (0.5 x 0.1112)
a = 761.3 m/s2
F = ma
F = 0.1153 x 761.3
F = 87.8 N
iv) How far horizontally from where it was dropped does the fish hit the water?
I can't seem to figure out a way to get this answer. Can someone please check if my answers are right and can give me an insight on how to answer this last question? Thank you!