16. A gear system has 36 teeth and 27 teeth and 18 and 12 respectively, what is the gear ratio between the 1st and 2nd gears and the 3rd and 4th gears?
A) .75 and .66
B).75 and 1.5
C) 1.33 and .66
D).75 and 3

Draw the engineering stress-strain curve for (a) bcc; (b) fcc metals and mark important points.

Awall of 0.5m thickness is to be constructed from a material which has average thermal conductivity of 1.4 w/mk. the wall is to be insulated with a material having an average thermal conductivity of 0.35 w/mk so that heat loss per square meter shall not exceed 1450 w. assume inner wall surface temperature of 1200°c and outer surface temperature of the insulation to be 15°c. calculate the thickness of insulation required.

Starting wih an energy balance on a rectangular volume element, derive the one- dimensional transient heat conduction equation for a plane wall with constant thermal conductivity and no heat generation.