15) Which one of the following is NOT the property of a good lubricant ?

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:

Becomes thicker after prolonged use

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.

With high pressure jet

With a brush

With an oilcan

Either 'B' or 'C'

Answer is:

Explanation:

With high pressure jet is common method for applying cutting fluid on the tool point .

Dry air

Kerosene

Machine oil

Soft water

Answer is:

Explanation:

While machining cast iron, the coolant used should be Dry air.