10) Which one of the following is the reason that tap water is not preferred as coolant on machine tool ?

It decreases cutting action of the tool

Danger of corrosion

It has insufficient cooling effect

Due to high cooling effect the cutting edges of the tool break off

Answer is:

Danger of corrosion

Explanation:

Danger of corrosion is the reason that tap water is not preferred as coolant on machine tool.

Sliding friction

Rolling friction

Fluid friction

Dry friction

Answer is:

Explanation:

Dry friction occurs in an un-lubricated journal bearing.

Tool steel

Grey cast iron

Copper

Aluminium

Answer is:

Explanation:

In Grey cast iron materials no cutting oil is used when drilling.

Cutting oil

Grease

Lard oil

Kerosene oil

Answer is:

Explanation:

when cutting steel with hand hacksaw, cutting oil is used .

Carry away the heat produced in bearing

Prevent metal-to-metal contact and reduce friction

Prevent entry of foreign material i.e dust, dirt etc. in the bearing

Provide a cushion to a load and shocks

Answer is: