Magnetism and Electromagnetism A permanent magnet Attracts some substances and repels others Attracts ferromagnetic substances and repels all others Attracts only ferromagnetic substances Attracts all paramagnetic substances and repels others Attracts some substances and repels others Attracts ferromagnetic substances and repels all others Attracts only ferromagnetic substances Attracts all paramagnetic substances and repels others ANSWER DOWNLOAD EXAMIANS APP
Magnetism and Electromagnetism A certain amount of current flows through a ring shaped coil with fixed number of turns. How does the magnetic induction B varies inside the coil if an iron core is threaded into coil without dimensional change of coil? Remains same Increases First increases and then decreases depending on the depth of iron in¬sertion Decreases Remains same Increases First increases and then decreases depending on the depth of iron in¬sertion Decreases ANSWER DOWNLOAD EXAMIANS APP
Magnetism and Electromagnetism Materials subjected to rapid reversal of magnetism should have Large area of B-H loop High co-ercivity and high retentivity High co-ercivity and low density High permeability and low hysteresis loss Large area of B-H loop High co-ercivity and high retentivity High co-ercivity and low density High permeability and low hysteresis loss ANSWER DOWNLOAD EXAMIANS APP
Magnetism and Electromagnetism A magnetic field exists around Moving Charges Aluminium Iron Copper Moving Charges Aluminium Iron Copper ANSWER DOWNLOAD EXAMIANS APP
Magnetism and Electromagnetism Which of the following type of materials are not very important for engineering applications? Ferro magnetic material Paramagnetic material None of the listed here Diamagnetic material Ferro magnetic material Paramagnetic material None of the listed here Diamagnetic material ANSWER DOWNLOAD EXAMIANS APP
Magnetism and Electromagnetism The electromagnet has 50 turns and a current of 1A flows through the coil. If the length of the magnet circuit is 200 mm, what is the magnetic field strength? 25 AT/m 250 AT/m 2500 AT/m 0.25 AT/m 25 AT/m 250 AT/m 2500 AT/m 0.25 AT/m ANSWER DOWNLOAD EXAMIANS APP