LIST OF IMPORTANT DERIVATIONSThat's a broad question dude, but still I'll try to help u outSome Imp derivations that u should know :1. Work done (dipole electric field) *2. Energy in capacitor **3. Wheatstone bridge (meter bridge)***4. Potentiometer****5. Bio savarts law ( for infinite wire, finite wire, loops etc)****6. Ampere law***7 solenoid***8. Cyclotron *****9. Magnetic force on charge particle**10. Moving coil galvanometer*****11. Energy stored in inductor**12. LC oscillator***13. AC generator*14. OPTICS lens maker formula***15. Prism min. Angle of deviation***16. Ydse experiment ***17. Npn transistor (amplifier , switch etc)*****18. Bohr model ( radius*** , velocity** , energy**** , time period *and Bohr magneton***)