Multiple Choice Question (MCQ)
Question: Calculate the depth of buttress thread diameter 30 mm of pitch 3mm?
A.
1.25 mm
B.
1.5 mm
C.
2.25 mm
D.
3.00 mm
Correct Answer: 2.25 mm
Explanation
When a liquid is contained in a vessel, it exerts force at all points on the sides and bottom of the vessel. The force per unit area is called intensity of pressure. Mathematically, intensity of pressure,
p = P/A
where
P = Force acting on the liquid, and
A = Area on which the force acts.
The intensity of pressure may be expressed either in N/m2, N/mm2 or in metres of liquid or mm of liquid. Intensity of pressure is also expressed in pascal (briefly written as Pa), such that
1 Pa= 1 N/m2; 1 kPa= 1 kN/m2 and 1 MPa = 1 MN/m2= 1 N/mm2