Two plates with symmetrical $$V$$ joint penetration of $$V$$ angle $$60deg$$ are to be arc welded in a single pass. The power $$P(kW)$$-arc length $$L$$ $$(mm)$$ characteristic is given by $$P=4+0.8L-0.1$$$${L^2}$$. Assuming that the top surface of the weld is flat & flush with the plate top surface, & the energy losses are $$20\% $$, the density of filler material is $$8gm/cc$$ and the energy required to melt $$1$$ $$gm$$ is $$1400$$ joules. The plate dimensions are $$1000mm$$ length & $$5mm$$ thickness. The maximum welding speed is .......................

The consumption of an oxy-acetylene flame for cutting of steel contains more oxygen

When the depth of cut is increased, the specific cutting energy

The material most commonly used for manufacturing of machine tool beds is