Machine Design
The circumferential and longitudinal strains in a cylindrical boiler under internal steam pressure are εc and εl respectively. The change in volume of the boiler cylinder per unit volume will be

2εc + εl
εc² + εl
εc + εl²
εc + 2εl

ANSWER DOWNLOAD EXAMIANS APP

Machine Design
Castle nut is a locking device in which

Through slots are made at top and a cotter pin is passed through these and a hole in the bolt, and cotter pin spitted and bent in reverse direction at other end
A slot is cut partly is middle of nut and then slot reduced by tightening a screw
One smaller nut is tightened over main nut and main nut tightened against smaller one by loosening, creating friction jamming
A hard fibre or nylon cotter is recessed in the nut and becomes threaded as the nut is screwed on the bolt causing a tight grip

ANSWER DOWNLOAD EXAMIANS APP