NEET-XII-Physics

38: Electromagnetic Induction

with Solutions - page 7
Qstn# iv-20-a Prvs-QstnNext-Qstn
  • #20-a
    the contact begins to slide and (b) it has slid through half the length of the rheostat.
    Figure
    Ans : For y = L,
    `` e=\frac{{\,\mathrm{\,\mu \,}}_{0}N\,\mathrm{\,\pi \,}{a}^{2}a{\mathit{\text{'}}}^{\mathit{2}}\epsilon Rv}{2L({a}^{2}+{x}^{2}{)}^{3/2}(R+r{)}^{2}}`` (b) For y = L/2,
    `` \frac{R}{L}y=\frac{R}{2}``
    `` \Rightarrow e=\frac{{\mu }_{0}N\pi {a}^{2}a{\text{'}}^{2}}{2L({a}^{2}+{x}^{2}{)}^{3/2}}\frac{\epsilon Rv}{{\left({\displaystyle \frac{R}{2}}+r\right)}^{2}}``
    Page No 307:
  • #20-b
    it has slid through half the length of the rheostat.
    Figure
    Ans : For y = L/2,
    `` \frac{R}{L}y=\frac{R}{2}``
    `` \Rightarrow e=\frac{{\mu }_{0}N\pi {a}^{2}a{\text{'}}^{2}}{2L({a}^{2}+{x}^{2}{)}^{3/2}}\frac{\epsilon Rv}{{\left({\displaystyle \frac{R}{2}}+r\right)}^{2}}``
    Page No 307: