The magnetic intensity at the center of a long current carrying solenoid is found to be $1.6 \times 10^{3} \mathrm{Am}^{-1}$. If the number of turns is 8 per cm, then the current flowing through the solenoid is __________ A.
Answer (integer)
2
Solution
<p>In a solenoid, the magnetic field intensity ($H$) is given by the product of the number of turns per unit length ($n$) and the current ($I$) flowing through the solenoid. This can be represented mathematically as:</p>
<p>$H = nI$</p>
<p>This is actually derived from Ampere's law applied to the special case of a solenoid, where the magnetic field is uniform and directed along the axis of the solenoid.</p>
<p>If we rearrange this equation to solve for the current ($I$), we get:</p>
<p>$I = \frac{H}{n}$</p>
<p>In this problem, we're given that the magnetic field intensity ($H$) at the center of the solenoid is $1.6 \times 10^{3} \, \text{Am}^{-1}$ and the number of turns per unit length ($n$) is 8 per cm (which is equal to $8 \times 10^{-2}$ per meter, as there are 100 cm in a meter).</p>
<p>Substituting these values into the equation gives:</p>
<p>$I = \frac{1.6 \times 10^{3} \, \text{Am}^{-1}}{8 \times 10^{-2} \, \text{turns/m}} = 2 \, \text{A}$</p>
<p>So, the current flowing through the solenoid is $2 \, \text{A}$.</p>
About this question
Subject: Physics · Chapter: Magnetism · Topic: Bar Magnet and Magnetic Field
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