Answered

Two identical light bulbs, each with resistance R = 2  are connected to a source with E = 8 V and negligible internal resistance. Find the current through each bulb, if the bulb in series and (ii) in parallel. ​

Answer :

  • R_1=R_2=2ohm
  • V=8V

In series

[tex]\boxed{\sf R=R_1+R_2}[/tex]

[tex]\\ \sf\longmapsto R=2+2[/tex]

[tex]\\ \sf\longmapsto R=4\Omega[/tex]

In parallel

[tex]\\ \sf\longmapsto \dfrac{1}{R}=\dfrac{1}{R_1}=+\dfrac{1}{R_2}[/tex]

[tex]\\ \sf\longmapsto \dfrac{1}{R}=\dfrac{1}{2}+\dfrac{1}{2}[/tex]

[tex]\\ \sf\longmapsto \dfrac{1}{R}=1[/tex]

[tex]\\ \sf\longmapsto R=1\Omega[/tex]

Now

Using ohms law

[tex]\boxed{\sf \dfrac{V}{I}=R}[/tex]

[tex]\\ \sf\longmapsto I=\dfrac{V}{R}[/tex]

In series:-

[tex]\\ \sf\longmapsto I=\dfrac{8}{4}[/tex]

[tex]\\ \sf\longmapsto I=2A[/tex]

In parallel

[tex]\\ \sf\longmapsto I=\dfrac{8}{1}[/tex]

[tex]\\ \sf\longmapsto I=8A[/tex]

Other Questions