Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
MHT CET 202626 AprilMorning Shift
Exam
MHT CET
Year
2026
Date
26 April
Shift
Morning Shift
Subject
Physics
Chapter
Magnetic Effects of Current

MHT CET 2026 · 26 April · Morning Shift · Physics · Magnetic Effects of Current

A circular coil having 'n' turns, each of radius 'r' carries a...

A circular coil having 'n' turns, each of radius 'r' carries a current 'I'. The magnetic field at a distance x=8 rx = \sqrt{8}\ r from its centre along axis of the coil is (μ0=(\mu_0 = permeability of free space)

Options

  1. Aμ0nI54 r\dfrac{\mu_0 nI}{54\ r}
  2. Bμ0nI27 r\dfrac{\mu_0 nI}{27\ r}
  3. Cμ0nI64 r\dfrac{\mu_0 nI}{64\ r}
  4. Dμ0nI36 r\dfrac{\mu_0 nI}{36\ r}

Correct answer

A. μ0nI54 r\dfrac{\mu_0 nI}{54\ r}

Step-by-step solution

The magnetic field at a distance xx on the axis of a circular coil of nn turns, radius rr, carrying current II is given by

B=μ0nIr22(r2+x2)3/2B = \dfrac{\mu_0 n I r^2}{2(r^2 + x^2)^{3/2}}

Given x=8rx = \sqrt{8} r, substituting this value in the formula:

B=μ0nIr22(r2+(8r)2)3/2B = \dfrac{\mu_0 n I r^2}{2(r^2 + (\sqrt{8} r)^2)^{3/2}}

B=μ0nIr22(r2+8r2)3/2B = \dfrac{\mu_0 n I r^2}{2(r^2 + 8r^2)^{3/2}}

B=μ0nIr22(9r2)3/2B = \dfrac{\mu_0 n I r^2}{2(9r^2)^{3/2}}

B=μ0nIr22(27r3)B = \dfrac{\mu_0 n I r^2}{2(27r^3)}

B=μ0nI54rB = \dfrac{\mu_0 n I}{54 r}

Answer: μ0nI54 r\dfrac{\mu_0 nI}{54\ r}
Practice Magnetic Effects of Current on Quantrex Academy →

More from Magnetic Effects of Current

The magnitude of the magnetic induction (B) at a point on the axis at a large distance… MHT CET Medical 2026For a circular coil of radius a , at what distance x along its axis the magnetic field is… MHT CET Medical 2026The ratio of cyclotron frequency f to the radius of the path of a charged particle R is… MHT CET Medical 2026In a cyclotron, for the same values of B and R, what is the ratio of the maximum kinetic… MHT CET Medical 2026The magnitude of the magnetic field at point O (centre of the arc) with radius R, in the… MHT CET Medical 2026Two wires of same material A and B, having lengths l and (2l)/(3) carry the currents I… MHT CET Medical 2026An electron is projected with uniform velocity along the axis of a current carrying long… MHT CET Medical 2026Two concentric coils, each of radius equal to 2π cm are placed at right angle to each… MHT CET Medical 2026 Full Magnetic Effects of Current list All MHT CET Medical PYQs