Some Physics Reminders

So, by way of text messaging a former student asked for some reminders about "forces and angles" in what I'm assuming is a unit or course in mechanics.

I'm not entirely sure of what exactly you're looking for but I'll take my best guess and you can reply below by leaving a comment about what you still need to know.

Forces are vectors. When you're determining the Net Force on an object you will need to use some trigonometry. Usually I find a good diagram helpful here since you can form a triangle out of the sum of two forces (provided they're not in the same or opposing directions)with the third side being their resultant.

From here you will need either the Sine Law, or the Law of Cosines. You can also use x and y components of the forces if you have more than two.

Explanations of the Sine Law and the Law of Cosines can be found by following the links.

If instead you're working with Inclined Planes (also involving forces and angles) you'll still want to draw a good diagram. With this topic, however, you'll be working with 'right angled trig' or as you may remember from high school the 'SOH CAH TOA' trigonometry.

The other topic I'm thinking you might be working with is Work. Work is the product of Force and displacement. Most questions in grade 12 involve the force and the distance being in the same direction, but if the force is at an angle to the displacement you will also need to include the cosine of the angle between them. The previous link may help.

I apologise for all of the references to wikipedia. On such short notice it's the best I can do. If you can post or email something more specific I could give you more detail. Hope this helped and good luck.