A cylinder of 100 mm diameter and 300 mm length rotates about a vertical axis inside a
fixed cylindrical tube of 105 mm diameter and
300 mm length. If the space between the tube
and the cylinder is filled with liquid of dynamic
viscosity of 0.125 N. s/mº, determine the speed
of rotation of the cylinder which will be obtained
if an external torque of 1 Nm is applied to it
[Ans. 81.03 r. p.m.)

If you were designing a bumper for a car, would you prefer it to exhibit elastic or plastic deformation? why? consider the functions of a bumper in both a minor "fender-bender" and a major collision.

What precautions should you take to prevent injuries when dealing with heavy loads?

Consider a large isothermal enclosure that is maintained at a uniform temperature of 2000 k. calculate the emissive power of the radiation that emerges from a small aperture on the enclosure surface. what is the wavelength ? , below which 10% of the emission is concentrated? what is the wavelength ? 2 above which 10% of the emission is concentrated? determine the wavelength at which maximum spectral emissive power occurs. what is the irradiation incident on a small object placed inside the enclosure?