Helicopter blades withstand tremendous stresses. in addition to supporting the weight of a helicopter, they are spun at rapid rates and experience large centripetal accelerations, especially at the tip. (a) calculate the magnitude of the centripetal acceleration at the tip of a 4.00 m long helicopter blade that rotates at 300 rev/min. (b) compare the linear speed of the tip with the speed of sound (taken to be 340 m/s).

Centripetal acceleration,

Explanation:

(a) The length of the helicopter blade, l = r = 4 m

Angular velocity of the blade,

The centripetal acceleration at the tip of the helicopter is given by :

Since,

(b) The linear speed of the tip of helicopter blade is given by :

v = 125.64 m/s

If the speed of sound is taken t o be 340 m/s, v' = 340 m/s

Comparison between linear speed of the tip to the speed of sound is :

Hence, this is the required solution.