The Grubler's criterion for determining the degrees of freedom (n) of a mechanism having plane motion is (where l = Number of links, and j = Number of binary joints)
n = 3(l - 1) - 2j
When the two elements of a pair have __________ when in motion, it is said to a lower pair.
A combination of kinematic pairs, joined in such a way that the relative motion between the links is completely constrained, is called a