Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NTA Abhyas JEE Main2020PhysicsMagnetic Effects of CurrentPractice

A ring of the radius R is placed in the y - z plane and it carries a current i . The conducting wires which are used to supply the current to the ring can be assumed to be very long and are placed as shown in the figure. The magnitude of the magnetic field at the centre of the ring A is

Options

  1. Aμ 0 i 4 π R 2 2 π 2 - 2 π + 1
  2. Bμ 0 i 4 π R 3 2 π 2 - 2 π + 1
  3. Cμ 0 i 3 π R 3 2 π 2 + 2 π - 1
  4. Dμ 0 i 3 π R 3 2 π 2 + 2 π + 1

Correct answer

A. μ 0 i 4 π R 2 2 π 2 - 2 π + 1

Step-by-step solution

​ Magnetic field due to wire along x - axis at A B → 1 = μ 0 4 π i R - k ^ , Magnetic field due to loop in y z - plane at A B → 2 = μ 0 4 π 2 π i R i ^ Magnetic field due to wire along z -axis at A B → 3 = μ 0 4 π i R - i ^ B → = B → 1 + B → 2 + B → 3 = μ 0 4 π i R 2 π - 1 i ^ + μ 0 4 π i R k ^ B = μ 0 4 π i R 2 π - 1 2 + 1 = μ 0 4 π i R 2 2 π 2 - 2 π + 1

Practice Magnetic Effects of Current on Quantrex Academy →

More from Magnetic Effects of Current

A hollow, right circular cone of base radius R and height h , with its tip at the origin is rotating about the Z -axis with an angular velocity , as shown in the figure. The cone c 2026In a vacuum chamber, a particle of charge 1 C and mass 1 mg is projected with a velocity ( i + 2 j ) ms ⁻¹ from the XZ plane at time t = 0 in an electric field of 1 i Vm ⁻¹ . At t 2026A current carrying circular loop of radius 2 cm with unit normal n = k + i 2 is placed in a magnetic field, B = B₀(3 i +2 k ) . If B₀ = 4 10⁻³ T and current I=100 2 A, the torque e 2026A 5 mg particle carrying a charge of 5 10⁻⁶ C is moving with velocity of (3 i +2 k ) 10⁻² m/s in a region having magnetic field B = 0.1 k Wb/m ^2 . It moves a distance of meter alo 2026A current of 30 A each flows in opposite directions in two conducting wires, placed parallel to each other at a distance of 8 cm. The magnetic field at the mid point between the tw 2026A small cube of side 1 mm is placed at the centre of a circular loop of radius 10 cm carrying a current of 2 A. The magnetic energy stored inside the cube is 10⁻¹⁴ J. The value of 2026The charged particle moving in a uniform magnetic field of (3 i + 2 j ) T has an acceleration (4 i - x 2 j ) m/s ^2 . The value of x is __________. 2026A circular coil of radius 2 cm and 125 turns carries a current of 1 A. The coil is placed in a uniform magnetic field of magnitude 0.4 T. The axis of the coil makes an angle of 30° 2026 Full Magnetic Effects of Current list All NTA Abhyas JEE Main PYQs