Theory of Machine
The two elements of a pair are said to form a higher pair, when they

Have a line or point contact when in motion
Permit relative motion
Have a surface contact when in motion
Are kept in contact by the action of external forces, when in motion

ANSWER DOWNLOAD EXAMIANS APP

Theory of Machine
Angle of descent of cam is defined as the angle

During which the follower returns to its initial position
Through which the cam rotates during the period in which the follower remains in the highest position
Of rotation of the cam for a definite displacement of the follower
Moved by the cam from the instant the follower begins to rise, till it reaches its highest position

ANSWER DOWNLOAD EXAMIANS APP