Question:-
To ensure self-locking in a screw jack it is essential that helix angle is
Option (A)
Larger than friction angle
Option (B)
Smaller than friction angle
Option(C)
Equal to friction angle
Option(D)
Such as give maximum efficiency in lifting
Correct Option:
(B)
Question Solution:
Æ > a [i.e. Friction Angle > Helix Angle]
tan Æ ³ tan a
tan Æ ³(np/pdm)
question-answer-faq-3240