Problem: The two objects in the figure below are balanced on the pivot, with m = 1.7 kg. What is distance d?

A Moment (torque) is the product of Force and Distance.

$\boxed{\begin{array}{rcl}\mathbf{\tau }& \mathbf{=}& \mathbf{F}\mathbf{·}\mathbf{r}\mathbf{ }\mathbf{s}\mathbf{i}\mathbf{n}\mathbf{ }\mathbf{\theta }\mathbf{ }\end{array}}$

$\boxed{\begin{array}{rcl}\mathbf{F}& \mathbf{=}& \mathbf{m}\mathbf{g}\end{array}}$

Let clockwise torque be positive and counter-clockwise torque be negative.

The system is in equilibrium. Therefore, the sum torque should be zero. 

$\boxed{\begin{array}{rcl}\mathbf{\Sigma \tau }& \mathbf{=}& \mathbf{0}\\ {\mathbf{\Sigma \tau }}_{\mathbf{cw}}\mathbf{-}{\mathbf{\Sigma \tau }}_{\mathbf{ccw}}& \mathbf{=}& \mathbf{0}\end{array}}$