Question

can somebody define the notion of symmetry for me for AP Physics?

Answer 1

Symmetry occurs when an object is still the same when you rotate or move it on an axis. Take a 2 dimensional plate for example (say with its vertical side longer), and from the center of it's vertical axis that plate is symmetric. As another example, a sphere is symmetric from its central point. In physics symmetry is used to simplify equations and solve them in an easier manner.

Take a uniform stick and nail it from its center of mass to a wall. When weights are added to its sides in equal amounts, you can see how the symmetry approach makes it very easy to solve. When you want to calculate torque through the center, and that stick is symmetrical from its center point, both sides have the same equation with the different masses. If those are equal as well, you can say: This stick has no torque on it based on the symmetry principle. Without the need for solving anything.

Answer 2

Thanks xD I had figured it out, haha, buuut thanks!