JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
Figure shows a current carrying square loop ABCD of edge length is ' \(a\) ' lying in a plane. If the resistance of the \(A B C\) part is \(r\) and that of \(A D C\) part is 2 r , then the magnitude of the resultant magnetic field at centre of the square loop is

- A \(\frac{3 \pi \mu_0 \mathrm{I}}{\sqrt{2} \mathrm{a}}\)
- B \(\frac{\mu_0 \mathrm{I}}{2 \pi \mathrm{a}}\)
- C \(\frac{\sqrt{2} \mu_0 \mathrm{I}}{3 \pi \mathrm{a}}\)
- D \(\frac{2 \mu_0 \mathrm{I}}{3 \pi \mathrm{a}}\)
Answer & Solution
Correct Answer
(C) \(\frac{\sqrt{2} \mu_0 \mathrm{I}}{3 \pi \mathrm{a}}\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{\mathrm{B}}=\overrightarrow{\mathrm{B}}_{\mathrm{AB}}+\overrightarrow{\mathrm{B}}_{\mathrm{BC}}+\overrightarrow{\mathrm{B}}_{\mathrm{CD}}+\overrightarrow{\mathrm{B}}_{\mathrm{DA}}\)…
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Physics
- A particle executes \(S.H.M.\) of amplitude A along \(x\)-axis. At \(t =0\), the position of the particle is \(x=\frac{A}{2}\) and it moves along positive \(x\)-axis the displacement of particle in time \(t\) is \(x=A \sin (\omega t+\delta)\), then the value \(\delta\) will beJEE Mains 2023 Medium
- A planoconvex lens becomes an optical system of \(28\, cm\) focal length when its plane surface is silvered and illuminated from left to right as shown in Fig \(-A\). If the same lens is instead silvered on the curved surface and illuminated from other side as in Fig. \(B\), it acts like an optical system of focal length \(10 \,cm\). The refractive index of the material of lens is
JEE Mains 2018 Hard - A cube has side length \(5\) cm and modulus of rigidity \(10^5\) N/m\(^2\). The displacement produced by a force of \(10\) N in the upper face of cube is _____ mm.JEE Mains 2026 Medium
- A mass of \(10\,kg\) is suspended vertically by a rope from the roof. When a horizontal force is applied on the rope at some point, the rope deviated at an angle of \(45^o\) at the roof point. If the suspended mass is at equilibrium, the magnitude of the force applied is .......... \(N\) \((g = 10\,ms^{-2})\)JEE Mains 2019 Medium
- The magnetic moment of an electron \((e)\) revolving in an orbit around nucleus with an orbital angular momentum is given by :JEE Mains 2022 Medium
- A convex lens of refractive index 1.5 and focal length \(f=18 cm\) is immersed in water. The difference in focal lengths of the given lens when it is in water and in air is \(\alpha \times f\). The value of \(\alpha\) is ___________.
(refractive index of water \(=4 / 3\) )JEE Mains 2026 Medium
More PYQs from JEE Mains
- Let \(A =\{ x \in R :| x +1|<2\}\) and \(B=\{x \in R:|x-1| \geq 2\}\). Then which one of the following statements is NOT true ?JEE Mains 2022 Medium
- If the equation of a plane \(P ,\) passing through the intesection of the planes, \(x+4 y-z+7=0\) and \(3 x+y+5 z=8\) is \(ax +b y+6 z=15\) for some \(a, b \in R,\) then the distance of the point \((3,2,-1)\) from the plane \(P\) isJEE Mains 2020 Medium
- The term independent of \(x\) in expansion of \({\left( {\frac{{x + 1}}{{{x^{2/3}} - {x^{\frac{1}{3}}} + 1\;}}--\frac{{x - 1}}{{x - {x^{1/2}}}}} \right)^{10}}\) isJEE Mains 2013 Hard
- A number \(x\) is chosen at random from the set \(\{1, 2, 3, 4, .... , 100\}\) . Define the event: \(A =\) the chosen number \(x\) satisfies \(\frac{{(x - 10)(x - 50)}}{{(x - 30)}} \ge 0.\) Then \(P(A)\) isJEE Mains 2014 Hard
- If the angle between the lines, \(\frac{x}{2} = \frac{y}{2} = \frac{z}{1}\) and \(\frac{{5 - x}}{{ - 2}} = \frac{{7y - 14}}{p} = \frac{{z - 3}}{4}\) is \({\cos ^{ - 1}}\,\left( {\frac{2}{3}} \right),\) then \(p\) is equal toJEE Mains 2018 Medium
- The number of natural numbers lying between \(1012\) and \(23421\) that can be formed using the digits \(2,3,4,5,6\) (repetition of digits is not allowed) and divisible by \(55\) is \(....\)JEE Mains 2022 Hard