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At the local swimming hole, a favorite trick is to run horizontally off a cliff that is 8.0 m above the water. One diver runs off the edge of the cliff, tucks into a "ball," and rotates on the way down with an average angular speed of 1.2 rev/s. Ignore air resistance and determine the number of revolutions she makes while on the way down.

User Rocker
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1 Answer

2 votes

Answer:

Number of revolutions=1.532 revolutions

Step-by-step explanation:

Given data

Distance s=8.0 m

Angular speed a=1.2 rev/s

To find

Number of revolutions

Solution

From the equation of simple motion we not that


S=ut+1/2gt^(2)\\ where\\u=0\\So\\8.0m=0+(1/2)(9.8m/s^(2) )t^(2)\\ t^(2)=(8.0m)/(0.5*9.8m/s^(2) ) \\ t^(2)=1.63\\t=√(1.63) \\t=1.28s

So for the number of revolutions she makes is given as


n=a*t\\n=(1.2rev/s)(1.28s)\\n=1.532revolutions

User GoFaster
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