Numerical Examples | Chapter 12 | Electromagnetism | Physics 11th | National Book Foundation 2025

For latest videos, click on the following link: https://whatsapp.com/channel/0029VaGr... A wire having a mass per unit length of 𝟎.𝟒𝟎𝟎𝒈/𝒄𝒎 carries a 𝟓.𝟎𝑨 current horizontally to the south. What is (a) the direction of force and (b) the magnitude of the minimum magnetic field perpendicular to the length of the conductor needed to lift this wire vertically upward? 12.2 An electron is accelerated through 𝟑𝟔𝟎𝟎𝑽 from rest and then enters a uniform 𝟐.𝟕𝟎𝑻 magnetic field. What are (a) the maximum and (b) the minimum values of the magnetic force this particle experiences? 12.3 A proton is moving in a circular orbit of radius 𝟏𝟐𝒄𝒎 in a uniform 𝟎.𝟒𝟎𝑻 magnetic field perpendicular to the velocity of the proton. Find the speed of the proton. 12.4 A horizontal power line carries a current of 𝟏𝟎𝟎𝑨 in an east to west direction. What is the magnitude and direction of magnetic field due to the current 𝟐.𝟎𝒎 below the line? 12.5 In a certain region the magnetic field is given by 𝑩 ⃗=(𝟒𝒊+𝟔𝒌)𝑾𝒃/𝒎^𝟐. How much magnetic flux passes through a 𝟐.𝟎𝒎^𝟐 area loop in this region if loop lies flat in xy plane? 12.6 A solenoid of circular cross-sectional radius of 𝟎.𝟖𝒎^𝟐 and 𝟑𝟎𝟎 turns is facing perpendicular to a magnetic field with magnetic flux density of 𝟒𝒎𝑻. Determine the magnetic flux linkage for this solenoid. 12.7 A coil of resistance 𝟓𝟎𝛀 is placed in magnetic field and initial magnetic flux of 2mWb. The coil has 150 turns and a galvanometer 0f 𝟏𝟎𝟎𝛀 resistance is connected in series with it. Find the average emf and the current if the coil is moved in 1/10th s from the given magnetic field to another field where final magnetic flux of 𝟒𝒎𝑾𝒃.