Question

In a four-bar linkage, S denotes the shortest link length, L is the longest link length, P and Q are the lengths of other two links. At least one of the three moving links will rotate by 360° if
1. S + L ≤ P + Q
2. S + L > P + Q
3. S + P ≤ L + Q
4. S + P > L + Q

Answer 1

Correct Answer - Option 1 : S + L ≤ P + Q

According to Grashoff’s Law for a four bar mechanism, the sum of shortest and longest link lengths should not be greater than the sum of the remaining two link length.

i.e. S + L ≤ P + Q