13) The effective cutting of steel with hand hacksaw, which one of the following coolants is suitable ?

Cutting oil

Grease

Lard oil

Kerosene oil

Answer is:

Cutting oil

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:

No change in viscosity due to variation in temperature

Reduces friction between machine parts

Takes up the surface pressure between sliding parts

Becomes thicker after prolonged use

Answer is:

Viscosity

Specific gravity

Specific heat

Emulsification

Answer is:

Explanation:

The most important quality of any lubricant is Viscosity.

Mix soluble oil and water by pouring both simultaneously

Add water to the soluble oil

Add soluble oil to the water

None of the above

Answer is:

Explanation:

Adding soluble oil to the water is one of the best way for preparing an emulsion.