The $$S$$-$$N$$ curve for steel becomes asymptotic nearly at

In a band brake the ratio of tight side band tension to the tension on the slack side is $$3.$$ If the angle of overlap of band on the drum is $${180^ \circ }$$ the coefficient of friction required between drum and the band is

In Oxyacetylene gas welding, temperature at the inner cone of the flame is around

A brass billet is to be excluded from its initial diameter of $$100mm$$ to a final diameter of $$50mm$$. The working temperature is $${700^ \circ }C$$ and the extrusion constant is $$250$$ $$MPa.$$ The force required for extrusion is