Questions are very useful: “what would happen if…” is the foundation of science, after all.
Conjectures and Refutations is a famous book by the late philosopher Sir Karl Popper. I could not possibly summarise it (heck, I haven’t even read it), but what I take away from what I’ve read and heard about it, is that theories can be judged on their predictive value. A theory in itself is no more than an intellectual exercise, but its real value lies in being able to apply it to what-if questions. The stronger a theory, the better it should predict outcomes. The way to “refute” a theory, is to come up with an example where it fails. Rinse and repeat, and you’ve captured the essence of science.
Want to predict what will happen when you place a 100 Ω resistor across a 9V battery? That’s easy, given the proper theory: take Ohm’s Law (i.e. a theory which has stood the test of time), and apply it – a current of
≈ 11 90 mA will flow. Actually a bit less due to the internal resistance of the battery, which goes to show how strong theories can be refined further, leading to even more accurate predictions.
The what-if question is a great way to experiment, especially in electronics and electro-mechanics, because it lets you be prepared and avoid silly (and sometimes catastrophic) outcomes, such as a damaged component, a harmful burn, or even an explosion.
This approach lends itself to all sorts of practical questions:
- What if I short out a 3x AA battery pack?
- What if I connect my chip the wrong way around?
- What if I have to use a 12V power supply instead of 5V?
But also issues as varied as:
- What if I omit a certain component from my circuit?
- What if I unplug the Raspberry Pi without shutting it down?
- What if I wanted to use HouseMon in combination with MySQL?
Properly phrased, what-if questions are essential for practical experiments, and – by extension – also the key to building useful circuits and automated installations.
A useful variation of the what-if question is to help predict “bad” outcomes and estimate the risk of an experiment, such as: can shorting out my power supply cause real damage?
Starting tomorrow, I’m launching a new series on this weblog, titled “What-If Wednesday”. As far as I’m concerned, it can run as long as there are interesting questions I can answer, so please feel free to suggest lots of topics in the comments below. These weekly posts will be tagged What-If, and I’m also setting up a new wiki page to collect them all.
Sooo… please help me out folks, and send in some nice what-if questions!