# Homework Help: To find out the forces in a link mechanism

1. Jun 10, 2013

### chiraganand

1. The problem statement, all variables and given/known data
The figure attached contains the link mechanicsm in static equilibrium. The forces F for the link 2 and Q has to be calculated. Given the length of link 2 is 4 cm and a moment of 50 Nm is applied to link 2

2. Relevant equations

3. The attempt at a solution
The attempt of solution is that at the pivot point 1 the force is resolved into two components the horizontal component and vertical component. We have a moment given to the link 2. Hence taking the summation of moments about the point B as zero we can find the horizontal and vertical components of the force and hence the resultant force acting on the link. to find the moment of the horizontal component and vertical components of the force we require the distance from the point B. I am unable to find this distance as it depends on the angle θ2 .

Hence i want to find the angle θ2 and i am unable to find it.

#### Attached Files:

• ###### figure of mechanism.jpg
File size:
14.5 KB
Views:
110
2. Jun 10, 2013

### chiraganand

Please someone help me out in this!!

3. Jun 15, 2013

### pongo38

You could try this: Identify a point K which is the intersection of the lines of action of members 2 and 4. This is actually the instantaneous centre of rotation of the triangle BCD with the 30 and 40 degree angles. Now, what happens when you take moments about K?