# 18.19 Capacitors and capacitance

Before you read this, I suggest you read post 17.44. A capacitor is a device for storing electrical charge (post 16.25); capacitance is the ability to store charge. But the amount of charge stored by a normal capacitor (its capacitance) is so small that the main application of capacitors is not to act as storage… Continue reading 18.19 Capacitors and capacitance

# 18.18 Who benefits from scientific research?

Different people will answer this question in different ways. Some people believe that all scientific research benefits everyone. At the other extreme, other people believe that most scientific research is harmful. I believe that most scientific research benefits somebody but, at the same time, some of it may have the potential to cause harm. Let’s… Continue reading 18.18 Who benefits from scientific research?

# 18.17 Euler’s relation, oscillations and waves

In post 18.15, we saw that the number e raised to the power x (see post 18.2) is defined by the series (post 17.11)           ex = 1 + x +x2/2! + x3/3! + x4/4! + x5/5! + … Here, for example, 5! = 5 × 4 × 3 × 2 × 1. In post… Continue reading 18.17 Euler’s relation, oscillations and waves