Expand the following: \begin{align} &\cssId{Step1}{{ I_{LED,3}=?}}\\[3px] &\cssId{Step2}{t_{bat,4} = {U_{bateries} – 5 U_{LED}\over 3 R}}\\[3px] &\cssId{Step3}{t_{bat,4} = {3U_{bat} – 5 U_{LED}\over 3 R}}\\[3px] &\cssId{Step4}{t_{bat,4} = 0,01532 A = 15,32 mA}\\[3px] \end{align}

- In the first step we make the equation of the force breaking with mass and acceleration
- In the seconde step we make the equation of normal force and the gravity force
- In the third step we make the equation of accelation with Force breaking and mass