The self inductance ' $L$ ' of a solenoid of length ' $l$ ' and area of cross-section 'A', with a fixed…
The self inductance ' $L$ ' of a solenoid of length ' $l$ ' and area of cross-section 'A', with a fixed number of turns ' $\mathrm{N}$ ' increases as
both $l$ and $\mathrm{A}$ increase
$l$ decreases and $\mathrm{A}$ increases
$l$ increases and A decreases
both $l$ and A decrease
Solution
The equation for self-inductance is:
$\mathrm{L}=\frac{\mu_0 \mathrm{~N}^2 \mathrm{~A}}{l}$
$\therefore \quad$ The self-inductance $\mathrm{L}$ of a solenoid of length $l$ and area of cross section ' $\mathrm{A}$ ', with a fixed number of turns " $\mathrm{N}$ ' increases as l decreases and $\mathrm{A}$ increases.
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