Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
Ofcourse use Ohms Law i.e. V=IR.
But that is not the only thing. You should also know the tolerance, wattage and package of the resistor.
If you are using the resistor across the measuring end, then the tolerance really play are greater role.
If you are using the resistor as current limiting, then the wattage matters, I2R.