Question

In your own words, describe the problem solving strategy you would use to find an unknown force in a mechanical system

Answer 1

The forces applied on a body will lead to either acceleration or shape change or both. Acceleration can be linear, rotational or both. So the first step is to identify the influence of the force on system.

Now suppose that the force applied causes a change in linear acceleration. We need to see the basic relation of force and acceleration for this seneario, which in this case is F=ma. So we will have to know the mass and find the acceleration, if not provided directly, by calculating the change in velocity. Then we will get the unknown force.

Suppose there are multiple forces acting and we dont know 1 of the forces. We will take the combined effect of the forces into account and co-relate it with the expression ∑F = ma to find the the unknown force.

Similarly if the force is causing a different effects (say rotation), we need to look into the basic relation of force under that effect and then proceed to solve the relevant equation.