Three resistance `R_1`, `R_2` and `R_3` are connected on parallel. Show that their equivalent resistance is `1/R=1/R_1+1/R_2+1/R_3`

Four resistance R_1,R_2,R_3 and R_4 are connected in parallel. The resultant resistance R is

Two resistance r_1 and r_2 (r1< r2) are joined in parallel. The equialent resistane R is such that

A piece of wire of resistance R is cut into five equal parts. These parts are then connected in parallel. If the equivalent resistance of this combination is R, then the ratio R/R' is

When two resistors of resistance R_1 and R_2 are connected in parallel, the net resistance is 3 ohm. When connected in series. Its values of 16 ohm. Calculate the value of R_1 and R_2 .

A galvanometer of resistance G is converted into a voltmeter to measure upto V volts by connecting a resistance R_1 in series with the coil. If a resistance R_2 s connected in series with it then it can measure upto V/2 volts Find the resistance R, in terms of R_1 and R_2 required to convert it into a voltmeter that can read upto 2V volts.

In the circuit given ahead, the resistors R_1 and R_2 are connected