Whenever some external system of forces acts on a body, it undergoes some deformation. As the body undergoes some deformation, it sets up some resistance to the deformation. This resistance per unit area to deformation, is called

strain
stress
pressure
modulus of elasticity
✅ The correct answer is option B.

A hollow saddle key is

a taper key which fits half in the key way of hub and half in the key way of shaft
a taper key which fits in a key way of the hub and is flat on the shaft
a taper key which fits in a key way of the hub and the bottom of the key is shaped to fit the curved surface of the shaft
provided in pairs at r
✅ The correct answer is option C.