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bearhunter [10]

3 years ago

14

I don't know how to do this. Working on #2

1 answer:

Mashcka [7]3 years ago

5 0

-- You know how much work the bow does on the arrow.

   Work = (force) x (distance) = (65 N) x (0.9 m)

-- THAT's the energy the arrow got from the bow, so
THAT's the kinetic energy the arrow has as it leaves the bow.

   KE = (1/2) (m) (speed)²

   so (1/2) (0.075 kg) (speed)² = (65 N) x (0.9 m)

The speed is the only thing left unknown in this mess.
I'm sure you can handle it from here, and find the speed.

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A plastic film moves over two drums. During a 4-s interval the speed of the tape is increased uniformly from v0 = 2ft/s to v1 =

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Answer:

Question 1)

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Answer:

1) current = I

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4) resistance = V/2I

5) current = 3I

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