Two blocks are arranged at the ends of a massless cord over a frictionless massless pulley as shown in the figure. Assume the system starts
from rest. When the masses have moved a distance of 0.433 m, their speed is 1.32 m/s.
The acceleration of gravity is 9.8 m/s
2
.
4 kg
2.6 kg
µ
What is the coefficient of friction between
m2 and the table?

Engines for propeller-driven aircraft are limited in their maximum rotational speed by the fact that the tip speed of the propeller must not approach the speed of sound in air (mach i). taking 6 ft as a typical diameter for a propeller of a light airplane and 1100 fils as the speed of sound, find the upper limit on the rpm (revolutions per minute) of the propeller shaft.