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3 years ago

6

Jane, looking for Tarzan, is running at top speed (4.9 m/s) and grabs a vine hanging 4.1 m vertically from a tall tree in the ju

ngle. If air resistance is neglected, how high can she swing upward? Hint: use the conservation of energy. m Does the length of the vine affect your answer?

1 answer:

Ann [662]3 years ago

4 0

Answer:

1.22375 m

Explanation:

v = Velocity = 4.9 m/s

g = Acceleration due to gravity = 9.81 m/s²

h = Height

In this system the kinetic and potential energy is conserved when Tarzan at the top of the swing

$\dfrac{1}{2}mv^2=mgh\\\Rightarrow h=\dfrac{v^2}{2g}\\\Rightarrow h=\dfrac{4.9^2}{2\times 9.81}\\\Rightarrow h=1.22375\ m$

The height of the swing is 1.22375 m

As it can be seen in the equation the length of the vine does not matter

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3 years ago

A 2 kg object traveling at 5 m s on a frictionless horizontal surface collides head-on with and sticks to a 3 kg object initiall

Svetlanka [38]

Answer: (d)

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2 years ago

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djyliett [7]

Answer:

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lapo4ka [179]

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2 years ago

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