More precisely it tells you that what you might have learned about electric fields deriving from electric potential becomes false if you have a variablemagneticfield.
更精确地说，电势产生电场，这一观点是错误的，如果忽略变化磁场的存在的话。
2
In this article, it is pointed out that calculating induced electric field caused by variablemagneticfield in constant velocity by analogical method is a simple method.
用类比方法来计算以恒定速率变化的磁场产生的感应电场是一个简便的方法。
3
"We've always known that the Earth's magneticfield is variable, constantly evolving in time," Raymond said.