A gear with $$84$$ teeth is to be machined using a milling process with indexing. The index plate has the following four hole circles: $$36,38, 42., 48.$$ The change gear ratio required is

Match the items in Group - $${\rm I}$$ and $${\rm I}$$ $${\rm I}$$

In a surface broaching process, a broach having $$5mm$$ pitch and cut per teeth $$0.05mm$$ is used for reducing the thickness by $$6mm.$$ If the length of the work piece is $$50mm$$ and the cutting speed is $$0.05m/s,$$ the time required / pass in seconds is

It is required to punch a hole of diameter $$10mm$$ on a sheet of thickness $$3mm.$$ The shear strength of the work material is $$420MPa.$$ The required punch force is