An infinite sequence of resistance is shown in the figure. The resultant resistance between $A$ and $B$ will be, when ${R_1} = 1\,ohm$ and ${R_2} = 2\,ohm$ ............. $\Omega$
Medium
Download our app for free and get startedPlay store
Let the resultant resistance be $R$. If we add one more branch, then the resultant resistance would be the same because this is an infinite sequence.

$\therefore \frac{{R{R_2}}}{{R + {R_2}}} + {R_1} = R \Rightarrow 2R + R + 2 = {R^2} + 2R$

$ \Rightarrow {R^2} - R - 2 = 0 \Rightarrow R = - 1$ or $R = 2\,ohm$

art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    In the network shown in the following figure, each resistance is $1\,ohm.$ The effective resistance between $A$ and $B$ is
    View Solution
  • 2
    A metal wire has a resistance of $35 \,\Omega$. If its length is increased to double by drawing it, then its new resistance will be (in $\Omega$)
    View Solution
  • 3
    Temperature coefficient at $0\,^oC$ is $0.00125\,^oC^{-1}$. At a temperature of $25\,^oC$ its resistance is $1\,\Omega $. Find the temperature at which resistance is $1.2\,\Omega $
    View Solution
  • 4
    With a potentiometer null point were obtained at $140\, cm$ and $180\, cm$ with cells of $emf$ $1.1 \,V$ and one unknown $X\, volts$. Unknown $emf$ is .............. $V$
    View Solution
  • 5
    There are $8$ equal resistances $R$. Two are connected in parallel, such four groups are connected in series, the total resistance of the system will be
    View Solution
  • 6
    What will happen when a $40\, watt$, $220\, volt$ lamp and $100\, watt$, $220\, volt$ lamp are connected in series across $40\, volt$ supply
    View Solution
  • 7
    An ammeter with internal resistance $90\,\Omega $ reads $1.85\, A$ when connected in a circuit containing a battery and two resistors $700\,\Omega $ and $410\,\Omega $ in series. Actual current will be
    View Solution
  • 8
    Consider the circuit given here with the following parameters $E.M.F.$ of the cell = $12\, V$. Internal resistance of the cell $ = 2\,\Omega $. Resistance $R = 4\,\Omega $ Which one of the following statements in true
    View Solution
  • 9
    After switch is closed, current drawn from the battery is (in $A$)
    View Solution
  • 10
    A student in a town in India, where the price per unit ( $1$ unit $=1 \,kWh$ ) of electricity is $₹ 5.00$, purchases a $1 \,kVA$ $UPS$ (uninterrupted power supply) battery. A day before the exam, $10$ friends arrive to the student's home with their laptops and all connect their laptops to the $UPS$. Assume that each laptop has a constant power requirement of $90 \,W$. Consider the following statements.

    $I.$ All the $10$ laptops can be powered by the $UPS$, if connected directly.

    $II.$ All the $10$ laptops can be powered, if connected using an extension box with a $3 \,A$ fuse.

    $III.$ If all the $10$ friends use the laptop for $5 \,h$, then the cost of the consumed electricity is about $₹ 22.50.$

    Select the correct option with the true statements.

    View Solution