diff --git a/02_lois_de_newton.md b/02_lois_de_newton.md
index 454a3aa28323e4486c6fd546f9ac912cfd42f0ec..dbfbac9cf09ca58d45d67dcfc0a06770da50bc28 100644
--- a/02_lois_de_newton.md
+++ b/02_lois_de_newton.md
@@ -1104,7 +1104,7 @@ Solution (La balle qui tourne) #
 
 Nous savons que la balle subit une force 
 $$
-F\mathrm{res}=m a_R=m \frac{v^2}{r}=m\frac{(2\pi r)^2}{T}\frac{1}{r}=\frac{4\pi^2 r}{T}=\frac{4\pi^2}{10}\cong 3.95\N.
+F\mathrm{res}=m a_R=m \frac{v^2}{r}=m\frac{(2\pi r)^2}{T}\frac{1}{r}=\frac{4\pi^2 r}{T}=\frac{4\pi^2}{10}\cong 0.395\N.
 $$
 
 ---