## 物理相关：电表改装。

（图片的微安表视为灵敏电流计，内阻为500Ω。量程为0～250μA。图例为灵敏电流计改装电压表。）

## 1. 电表

（a）就是右边（b）的原型，灵敏电流计。厂商首先生产灵敏电流计，然后通过连接电阻的方式，来改装成电流表或是电压表。它的内阻很小，而量程也不大，有的十分小，0～3μA，有些大一些，0～2mA。（本例中的电流计量程为0～250μA）

## 2. 电表改装

### （1）电流表改装

（图片的微安表视为灵敏电流计，内阻为500Ω。量程为0～250μA。图例为灵敏电流计改装电流表。）

### （2）电压表

（解释略）如图改装以后，电流计所在支路就可以视作一个电压表了。只需要将表盘上的示数修改即可。

## 3. 总结

$\dfrac{U_1}{U_2}=\dfrac{R_1}{R_2}$

Lake桑

2018.12.5

## 每日一词：abandon（转自 韦氏词典）

Merriam-Webster’s Word of the Day for December 5, 2018 is:

abandon • \uh-BAN-dun\  • noun

: a thorough yielding to natural impulses; especially : enthusiasm, exuberance

Examples:

The winning photograph was of a dog bounding with abandon through a field of snow.

“The drum solo has long been a concert punchline. Foo Fighters, in recognition of that, made Hawkins’ solo as ridiculous and over the top as possible. His drum kit, perched upon a hydraulic lift, soared twenty feet in the air as he pounded the skins with reckless abandon.” — Jim Ryan, Forbes, 19 Oct. 2018

Did you know?

The sense of abandon defined above is a relative newcomer to the English language, dating from the early 1800s, but an earlier noun sense, defined as “the act of abandoning,” was in use in the 1600s. The earlier sense was influenced by the verb abandon, which was borrowed by Middle English in the 1300s from Anglo-French abanduner. The Anglo-French term in turn came from the phrase (mettre) a bandun, meaning “to hand over” or “to put in someone’s control.” The newer sense has been more directly influenced by French abandon, which means not only “abandonment or surrender” but also “freedom from constraint.”

Lake桑

December 05, 2018 at 01:00PM