It has been established that a hole to be tapped must be smaller than the desired thread diameter. For example: a 5/16" hole must be drilled for a 3/8-16UNC thread. How much
larger must a shaft be machined to receive a 3/8-16UNC external thread? Why?

During a steady flow process, the change of energy with respect to time is zero. a)- true b)- false

Shafts are machine elements that are used to a) carry axial loads b) direct shear loads c) transmit power d) rotate at constant speed e) none of the above circular and square shafts subjected to the same torque under the same circum behave a) the same way b) almost the same way

Compute the pressure drop of 30°c air flowing with a mean velocity of 8 m/s in a circular sheet-metal duct 300 mm in diameter and 15 m long. use a friction factor, f 0.02, and pair = 1.1644 kg/m a. 37.26 pa b. 25.27 pa n c. 29.34 pa d. 30.52 pa