Question

state the law of combination of resistance in parallel​

Answer 1

Answer:

1/Rp=1/R1+1/R2 is the formula for calculating resistance when the resistors are in parallel

Answer 2

Resistance is basically an obstruction offered by the material in movement of electrons now these resistances can be combined in two ways one is series connection and other is parallel connection in series connection one input of resistance is connected to output of the other resistance while in case of parallel all the inputs are connected together all the outputs are connected together.  

To find the equivalent resistance when connected in parallel the inverse of all the resistances are added.  

$\frac{1}{R}=\frac{1}{R 1}+\frac{1}{R 2}+\frac{1}{R 3}$..so on