Strength of Materials
The effort required to lift a load W on a screw jack with helix angle a and angle of friction<="" div="">

Wcos(a + )
Wtan(a-<)>)
Wtan(a + <)>)
Wsin(a + <(>)

ANSWER DOWNLOAD EXAMIANS APP

Strength of Materials
Limiting force of friction is the

the friction force acting when the body is in motion
The friction force acting when the body is just about to move
Ratio of limiting friction and normal reaction
Tangent of angle between normal reaction and the resultant of normal reaction and limiting friction

ANSWER DOWNLOAD EXAMIANS APP