diff --git a/Homework/homework_13_forces_and_torques_on_currents/loop_work.py b/Homework/homework_13_forces_and_torques_on_currents/loop_work.py
index f2afeb4..320c9bd 100644
--- a/Homework/homework_13_forces_and_torques_on_currents/loop_work.py
+++ b/Homework/homework_13_forces_and_torques_on_currents/loop_work.py
@@ -6,7 +6,7 @@
 B = 1.3
 
 
-A = sqrt(3) * d**2/4
+A = (sqrt(3)/4) * (d**2) 
 mu = I * A
 
-print(- mu * B * cos( radians(180)))
+print( mu * B * (cos( radians(180)) - 1))