Two sheets of low carbon steel $$1.5mm$$ thick each are spot welded by passing a current $$10000$$ amps for $$5$$ cycles in $$50$$ $$Hz$$ main supply.

i) What is the heat generated due to the supply of power if effective resistance has $$200$$ micro ohms,

ii) The maximum indentation is $$10\% $$ of sheet thickness and density of the spot weld nugget $$8$$ $$gm/cc.$$ If $$1380$$ Joules are required to melt $$1gm$$ of steel, determine heat required for welding operation if $$D=6SQRT$$ $$(t)$$ to determine nugget diameter $$D$$ and assume the nugget size to be equal to metal between the two electrodes

In $$MIG$$ welding the power source characteristics is $${V_p} = 36 - {\rm I}/60$$ and the arc characteristics is $${V_a} = 2{L_a}\,\,\,\, + 27.$$ Find the change in power of the arc if the arc length changed from $$2mm$$ to $$4mm.$$ If the maximum current capacity of the power source is $$300$$ Amps, the maximum arc length sustainable is

In metal cutting with a carbide tool, at the maximum recommended speed, the largest $$\% $$ of heat generated goes to the

A generalized tool life equation for carbide tool for machining steel is given by
$$\,\,\,\,\,\,\,\,\,\,$$$$\,\,\,\,$$ $$V{T^a}{F^b}{D^c} = K,$$
Where $$V=$$ Cutting speed, meters/min,
$$\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,$$ $$T=$$ Tool life,
$$\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,$$ $$F=$$ feed, $$mm/rev,$$
$$D=$$ depth of cut in $$mm,$$ Indicates have magnitude $$a=0.3, b=0.3, c=0.15,$$

If the feed is halved and depth of cut doubled, for identical tool life of $$60$$ minutes, the percentage change in speed