Physic Labs

Problem 2

Two resistors R1,R2R_1,R_2 are connected in parallel to an ideal source of voltage VV. Find the equivalent resistance and total power. Use an idealized laboratory-frame model: stated parameters remain constant during the process unless the motion itself makes a quantity vary. State a clear sign convention and use the defined symbols consistently. (a) Write the governing laws or constraints. (b) Derive the requested quantities symbolically and state their physical direction or meaning. (c) Check dimensions and examine a simple physical limit to validate the result. Finally, verify that every equation is dimensionally consistent and that the results satisfy the initial conditions. Since no numerical data are specified, the exact answers are expressions in the defined symbols.
Req=R1R2R1+R2R_{\rm eq}=\tfrac{R_1R_2}{R_1+R_2}
problems.proof.analysis

Insert the initial conditions and stated constraints into the governing equation to relate known quantities to the unknowns. These conditions select the physically relevant solution among the algebraic possibilities.