题目4单选题
闭合曲面<img src="https://tihai-oss-cloud.itihey.com/img/2d44d72acf9ae7be7c0ea7bf7b7dbab7.png">包围点电荷<img src="https://tihai-oss-cloud.itihey.com/img/09ae1c8b7aa44dc11a18c5c63a7dd64c.png">, 现从无穷远处引入另一点电荷<img src="https://tihai-oss-cloud.itihey.com/img/7412985d0ba37b933fde78747e4169d6.png">至曲面外一点,如图所示,则引入前后[ ]<img src="https://tihai-oss-cloud.itihey.com/img/116dc5fe980bffdd4bc6c76e1d1ad8ac.jpg">A. 曲面 <img src="https://tihai-oss-cloud.itihey.com/img/2d44d72acf9ae7be7c0ea7bf7b7dbab7.png">的电场强度通量不变,曲面上各点电场强度不变B. 曲面 <img src="https://tihai-oss-cloud.itihey.com/img/2d44d72acf9ae7be7c0ea7bf7b7dbab7.png">的电场强度通量变化,曲面上各点电场强度不变C. 曲面 <img src="https://tihai-oss-cloud.itihey.com/img/2d44d72acf9ae7be7c0ea7bf7b7dbab7.png">的电场强度通量变化,曲面上各点电场强度变化D. 曲面 <img src="https://tihai-oss-cloud.itihey.com/img/2d44d72acf9ae7be7c0ea7bf7b7dbab7.png">的电场强度通量不变,曲面上各点电场强度变化