A)The diameters of the main rotor and tail rotor of a single-enginehelicopter ar

Question

A)The diameters of the main rotor and tail rotor of a single-enginehelicopter are 7.56 m and 1.04 m, respectively. The respective rotational speedsare 440 rev/min and 4149 rev/min. Calculate the speeds of the tips of bothrotors. main rotor 1 m/s tail rotor 2 m/s Compare these speeds with the speed of sound, 343 m/s. vmain rotor /vsound 3 vtail rotor /vsound 4



B)A centrifuge in a medical laboratory rotates at an angular speedof 3750 rev/min. When switched off, itrotates through 54.0 revolutions beforecoming to rest. Find the constant angular acceleration of thecentrifuge.
1rad/s2 main rotor 1 m/s tail rotor 2 m/s

Explanation / Answer

You are going to use these two equations for circularmotion: V=r & ac=v2/r ; one 1revolution is 2 a) So for main tail rotor velocity is convert 440 rpms to rad/s so this is (440 rpm/1 min)(2/1revolution)(1 min/60 sec) = 46.0 rad/s radius is7.56m. Plugging this into the formula, weget V= r = (46.0 rad/s)(7.56 m) = 347 m/s For the tail rotor 4149 rpm to rad/s is 434.4 rad/s V= r = (434.4 rad/s)(1.04 m) = 451.8 m/s b) 3750 rpm to rad/s is 392.7 rad/s and 54 rpm to rad/s is 5.65rad/s wf2 - wo2=2 0 - (5.65)2 = 2(392.7) = - ((5.65)2/ 2(392.7) = - 0.041rad/s2 Hope this was helpful!

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---