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melomori [17]
4 years ago
12

A string trimmer is a tool for cutting grass and weeds; it utilizes a length of nylon "string" that rotates about an axis perpen

dicular to one end of the string. The string rotates at an angular speed of 38 rev/s, and its tip has a tangential speed of 69 m/s. What is the length of the rotating string?
Physics
1 answer:
olga2289 [7]4 years ago
4 0

Answer:

0.28899 m

Explanation:

v = Velocity = 69 m/s

\omega = Angular velocity = 39\times 2\pi\ rad/s

r = Radius of the motion

In rotational motion velocity is given by

v=r\omega

\\\Rightarrow r=\dfrac{v}{\omega}

\\\Rightarrow r=\dfrac{69}{38\times 2\pi}

\\\Rightarrow r=0.28899\ m

The length of the rotation string is 0.28899 m

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Given that,

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Answer:

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