Machine Design
In the calculation of induced shear stress in helical springs, the Wahl's stress factor is used to take care of

Combined effect of bending stress and curvature of the wire
Combined effect of transverse shear stress and curvature of wire
Combined effect of torsional shear stress and transverse shear stress in the wire
Combined effect of transverse shear stress and bending stress in the wire

ANSWER DOWNLOAD EXAMIANS APP

Machine Design
For same pulley diameters, center distance, belt speed and belt and pulley materials,

Power transmission does not depend upon open and crossed types of constructions
Open and crossed belt drives transmit same power
Open belt drive transmits more power than crossed belt drive
Crossed belt drive transmits more power than open belt drive

ANSWER DOWNLOAD EXAMIANS APP