Question { DRDO, 12916 }

You have to design a machine component. For what type of
failure (ductile or brittle) you will design?

Answer

If we see stress/strain diagram for both (ductile and
brittle), the most common region in both is elastic region.

Take ductile material:-
While designing any component we have to consider yield
strength. Not ultimate tensile strength.
It means we are designing for elastic region.

Take Brittle material:-
This is having only elastic region, so we have to design
for this region only.

If we conclude, we have to design a component for an
elastic region, so we can say for both, ductile as well as
brittle.

Question { 6775 }

bearings types

Answer

The basic types of bearings are

1) rolling contact bearing
2) Sliding contact bearing

All above mentioned bearings come under rolling contact
bearing.

Question { 18841 }

How many volts required to fire spark plug.

Answer

25 kV under occasional operating conditions.