Chapter intro: Forces and their effects

The first chapter taught you how to write a measurement down, and the second taught you how to describe motion. Neither one said why anything starts moving, stops, stretches or turns. The answer to all four is a force. This is Forces and their effects, the chapter where forces get named, added up, drawn, and finally made to turn things.

Here's the whole chapter laid out on your screen, plus a couple of things worth knowing before you press play on the first video.

It opens with contact and non-contact forces. Next comes weight, mass and gravitational field strength. Then you add forces up into one single resultant force, the one force that does the job of all of them. Free body diagrams come next, and that one is marked Higher. So is resolving forces with a scale drawing, the second Higher video. After that, the chapter turns to elastic and inelastic deformation. Hooke's law and the spring constant follows, and that is where the videos for every student end. Then moments. From here on, the chapter is separate physics only. Levers and gears close the chapter.

One practical thing first: every video here carries its own short, searchable code, sitting right beside its title. Take the spring one. Search ScholaFly P H oh three, oh seven, and that exact video comes straight up.

The other trick is the thumbs-up sitting on each video. Once something has properly landed for you, tap it, and that video marks itself as done. Anything left without a thumbs-up naturally becomes your revision list. If something hasn't clicked yet, save it to a playlist, because plenty of this settles on a second watch a few days later. And my commitment to you is this: if I've not done a great job teaching something and it's confusing, leave a comment, and I'll have a crack at making a better video.

Next in the chapter is Contact and non-contact forces. Hopefully that's next in your feed, but if not, search for ScholaFly P H oh three, oh one.

For more, visit scholafly.com, or watch the next video.