[Bob the Science Guy] remember how to use a slide rule. Even after all these years, it’s pretty easy to remember how to multiply and divide. If you can’t remember, you can usually work it out as long as you understand how the slide rules work. But what about sine, cosine and square? [Bob’s] have made videos on topics like this, and if you’ve been wanting to put your slide rule collection to practical use, you’ll enjoy these videos. You can see one below.
The trick to the slide rule is that it’s deceptively simple. You effectively add logarithms and then take an antilog. The problem is that you still need to have some intuition about the scale of the answer, because 2 × 3 works the same as 2 × 3000 or 200 × 300.
But it’s even more complicated than that. Adding and subtracting is not easy on the slide rule. [Bob] shows how to use your math skills to convert problems that would have been addition problems into trig problems. So if it seems more complicated to use trig, it can help to work the problem on the slide rule.
We like slide rules. If you don’t have one, try this one in your browser (tip: go full screen and show both pages).