Question bank/JEE Main/Physics

A uniform magnetic field B in positive z direction exists in a
circular region of radius R = 5 m. A loop of radius R = 5m lying in x -
y plane encloses the magnetic field at t = 0 and then pulled at uniform. The emf induced (in volts) is the
loop at t = 2 sec is 6V. Then magnitude of 4B is

Your answerCheck answer

Show answer and solution▾

$= VB2\sqrt{R^{2} - \left( \frac{vt}{2} \right)^{2}} = VB\sqrt{4R^{2} - V^{2}t^{2}}$
$6V = 4 \times B\sqrt{4 \times 25 - 16 \times 4}$
$B = 0.25T$

Source: Grass-G / P-13 Physics paper 4 Nov.docx