2. Solved Papers
  3. CEE Kerala Engineering

CEE Kerala Engineering CEE Kerala Engineering Solved Paper-2006

  • question_answer
    Two identical cells whether connected in parallel or in series gives the same current when connected to an external resistance\[1.5\,\Omega \]. Find the value of internal resistance of each cell.

    A)  \[1\,\Omega \]               

    B)         \[0.5\,\Omega \]

    C)  zero                     

    D)         \[2\,\Omega \]

    E)  \[1.5\,\Omega \]

    Correct Answer: E

    Solution :

    Let n cells be in series and m in parallel, then \[\frac{nE}{R+nr}=\frac{E}{R+\frac{r}{m}}\] \[\Rightarrow \]               \[n\left[ R+\frac{r}{m} \right]=R+nr\] \[\Rightarrow \]               \[nRm+nr=Rm+mnr\] \[\Rightarrow \]               \[6+2r=3+4r\] \[\Rightarrow \]               \[2r=3\] \[\Rightarrow \]               \[r=1.5\,\Omega \]


You need to login to perform this action.
You will be redirected in 3 sec spinner