diff --git a/10.brainstorming-innovative-courses/intercambio-curso-electromagnetismo/textbook.en.md b/10.brainstorming-innovative-courses/intercambio-curso-electromagnetismo/textbook.en.md
index 8c6b060f1..b2354afcb 100644
--- a/10.brainstorming-innovative-courses/intercambio-curso-electromagnetismo/textbook.en.md
+++ b/10.brainstorming-innovative-courses/intercambio-curso-electromagnetismo/textbook.en.md
@@ -696,7 +696,7 @@ $`\displaystyle\oiint_S\overrightarrow{B}\cdot\overrightarrow{dS}=0`$
 $`\displaystyle\iiint_{\tau} div\overrightarrow{E} \cdot d\tau= \displaystyle\iiint_{\tau} \dfrac{\rho}{\epsilon_0} \cdot d\tau = \dfrac{1}{\epsilon_0} \cdot \iiint_{\tau} \rho \cdot d\tau = \dfrac{Q_{int}}{\epsilon_0} `$
 
 
-$`\displaystyle\iint_S \overrightarrow{rot} \,\overrightarrow{E}\cdot \overrightarrow{dS} = -\displaystyle\iint_{S \leftrightarrow \tau} \overrightarrow{B}\cdot \overrightarrow{dS}`$
+$`\displaystyle\iint_S \overrightarrow{rot} \,\overrightarrow{E}\cdot \overrightarrow{dS} = -\displaystyle\iint_{S \leftrightarrow \tau} \dfrac{\partial \overrightarrow{B}}{\partial t}\cdot \overrightarrow{dS}`$
 
 Mecánica newtoniana : espacio y el tiempo son desacoplados $`\Longrightarrow`$ orden de integración / derivación entre variables de espacio y tiempo no importa.