Need help with Math

Good morning,

I am not very good at math, but still tried to do some trigonometry. However Math.sin() does not really give me the values I expect.

System.println( "**** sin(10)=" + Math.sin( 10 ) );

Gives me:

**** sin(10)=-0.544021

But according to my calculator, sin(10) = 0,1736...

So why does Monkey C give me -0,5440?? What am I doing wrong here?