The diameters of the main rotor and tail rotor of a single-engine helicopter are 7.67 m and 1.01 m, respectively. The respective rotational speeds are 455 rev/min and 4,140 rev/min. Calculate the speeds of the tips of both rotors.

main rotor	m/s
tail rotor	m/s

Compare these speeds with the speed of sound, 343 m/s.

vmain rotor	=	vsound
vtail rotor	=	vsound