A four bar mechanism is shown below. For the mechanism to be a crank-rocker mechanism, the length of the link PQ can be

Answer :

Solution :

For Crank-Rocker mecchanism, shortest link must be crank and adjacent to fixed as well as Grashoff's law must be satisfied.

If I = 80 mm

then shortest will be = 80 mm

as well as (80 + 600) < (400 + 300) 680 < 700

Therefore law is satisfied.

⇒ I = 80 mm