Physics
Water pipes in hilly areas often burst on a cold frosty night, because

Water in the pipes freezes and on freezing water expands, so pipes break
None of these
Frost makes the pipes rusty, so they break
The material of which pipes are made contracts due to cold and so breaks

ANSWER DOWNLOAD EXAMIANS APP

Physics
The Hooke's law is valid for

Elastic as well as plastic region of the stress strain curve
Entire elastic region of the stress strain curve
Only proportional region of the stress strain curve
Entire stress strain curve

ANSWER DOWNLOAD EXAMIANS APP