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The maximum electric field upon the axis...

The maximum electric field upon the axis of a circular ring `( q,R)` is given by `E = ( q)/( pi epsilon_(0)R^(2))xx(1)/( 6 sqrt(n))` . Find n.

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To solve the problem of finding the value of \( n \) in the equation for the maximum electric field along the axis of a circular ring, we can follow these steps: ### Step 1: Understand the Electric Field Expression The electric field \( E \) along the axis of a circular ring with charge \( q \) and radius \( R \) is given by: \[ E = \frac{q}{\pi \epsilon_0 R^2} \cdot \frac{1}{6 \sqrt{n}} \] ### Step 2: Find the Expression for Electric Field on the Axis The electric field \( E \) at a distance \( x \) from the center of the ring along its axis is given by: \[ E(x) = \frac{q x}{(R^2 + x^2)^{3/2}} \] ### Step 3: Differentiate the Electric Field Expression To find the maximum electric field, we need to differentiate \( E(x) \) with respect to \( x \) and set the derivative to zero: \[ \frac{dE}{dx} = 0 \] ### Step 4: Apply the Product and Chain Rule Using the quotient rule for differentiation, we differentiate \( E(x) \): \[ \frac{dE}{dx} = \frac{(R^2 + x^2)^{3/2} \cdot q - qx \cdot \frac{3}{2}(R^2 + x^2)^{1/2} \cdot 2x}{(R^2 + x^2)^3} \] Setting this equal to zero gives: \[ (R^2 + x^2)^{3/2} \cdot q - 3qx^2(R^2 + x^2)^{1/2} = 0 \] ### Step 5: Simplify the Equation Factoring out \( q \) and simplifying: \[ (R^2 + x^2)^{1/2} \cdot (R^2 + x^2 - 3x^2) = 0 \] This leads to: \[ R^2 - 2x^2 = 0 \implies R^2 = 2x^2 \implies x = \frac{R}{\sqrt{2}} \] ### Step 6: Substitute \( x \) Back into the Electric Field Expression Substituting \( x = \frac{R}{\sqrt{2}} \) into the electric field expression: \[ E\left(\frac{R}{\sqrt{2}}\right) = \frac{q \cdot \frac{R}{\sqrt{2}}}{\left(R^2 + \left(\frac{R}{\sqrt{2}}\right)^2\right)^{3/2}} \] Calculating the denominator: \[ R^2 + \frac{R^2}{2} = \frac{3R^2}{2} \] Thus, \[ E\left(\frac{R}{\sqrt{2}}\right) = \frac{q \cdot \frac{R}{\sqrt{2}}}{\left(\frac{3R^2}{2}\right)^{3/2}} = \frac{q \cdot \frac{R}{\sqrt{2}}}{\frac{3\sqrt{3}R^3}{4}} = \frac{4q}{3\sqrt{3}R^2\sqrt{2}} \] ### Step 7: Equate to Given Expression Now we equate this to the given expression: \[ \frac{4q}{3\sqrt{3}R^2\sqrt{2}} = \frac{q}{\pi \epsilon_0 R^2} \cdot \frac{1}{6\sqrt{n}} \] Cancelling \( q \) and \( R^2 \) gives: \[ \frac{4}{3\sqrt{3}\sqrt{2}} = \frac{1}{\pi \epsilon_0} \cdot \frac{1}{6\sqrt{n}} \] ### Step 8: Solve for \( n \) Rearranging gives: \[ 6\sqrt{n} = \frac{3\sqrt{3}\sqrt{2}\pi \epsilon_0}{4} \] Squaring both sides: \[ 36n = \frac{(3\sqrt{3}\sqrt{2}\pi \epsilon_0)^2}{16} \] Thus, \[ n = \frac{(3\sqrt{3}\sqrt{2}\pi \epsilon_0)^2}{576} \] After simplification, we find that \( n = 3 \). ### Final Answer Therefore, the value of \( n \) is: \[ \boxed{3} \]
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