a) calculate the centipetal acc at the tip of a 4.00 m long helicopter blade that rotates at 300 rpm.(adsbygoogle = window.adsbygoogle || []).push({});

300 rpm = 31.42 rad/s = w

Centrip Acc = rw^2

Ac = (3.41 rad/s)^2 * 4 m

Ac = 3948.87 m/s^2

b)compare linear speed of the tip with the speed of sound which is 340 m/s

v=rw

v = 4m * (31.42 rad/sec) = 125.28 m/s

So the blades are slower than the speed of sound.

This does not sound right to me I figured the blades would be faster - but maybe just not at the tip???

Thanks

Nautica

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# Centripetal Acceleration calculation help

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