介電常數

介 = 人 + 丿 + 丨 : Mnemonic symbol: 介 looks like a rocket 🚀. Neanderthal Man (人) and Joan of Arc (ji) are preparing a rocket (介) for its start. Between (介) the layers of the outer shell (介) they are stuffing bananas (丿) and dinosaur bones (丨).

电 = 乚 + 曰 : Dorothy Gale (di) is looking for a wall plug for her charger (mnemonic symbol for 电) in the anthill's bathroom (an4). She's digging up the whole place with a shovel (乚), but instead of a wall plug she finds a microphone (曰).

常 = 小 + 冖 + 吊 : Mnemonic symbol: the centennial light, a light bulb which will shine forever and ever.

常 = 小 + 冖 + 吊 : Charlie Chaplin is fighting his way through anglepod's underbrush with a coat hanger. The anglepod has not been visited in a hundred years, and with his coat hanger, Charlie Chaplin has to cut down a lot of daisies. Finally he found what he was looking for: the centennial light, protected from the daisies and the rain by a cooking top.

数 = 娄 + 攵 : Sheldon Shrimp (shu) occupied a lunar mansion (娄) inside of the space station (Ø3) although he knows that it is to be torn down. Outside of his lunar mansion the construction (or rather destruction) workers are already counting (数) down from ten. When they count (数) zero, they will start taking down the whole thing with their sledgehammers (攵).