Magnetism and Electromagnetism When the current through the coil of an electromagnet reverses, the magnetic field expands direction of the magnetic field reverses magnetic field collapses direction of the magnetic field remains unchanged magnetic field expands direction of the magnetic field reverses magnetic field collapses direction of the magnetic field remains unchanged ANSWER DOWNLOAD EXAMIANS APP
Magnetism and Electromagnetism What will be the current passing through the ring shaped air cored coil when number of turns is 800 and ampere turns are 3200? 6 4 8 12 6 4 8 12 ANSWER DOWNLOAD EXAMIANS APP
Magnetism and Electromagnetism The materials having low retentivity are suitable for making Weak magnet Temporary Magnet Permanent magnet None of the listed here Weak magnet Temporary Magnet Permanent magnet None of the listed here ANSWER DOWNLOAD EXAMIANS APP
Magnetism and Electromagnetism A 300 mm long conductor is carrying a current of 10 A and is situated at right angles to a magnetic field having a flux density of 0.8 T ; the force on the conductor will be 240 N 2.4 N 24 N 0.24 N 240 N 2.4 N 24 N 0.24 N ANSWER DOWNLOAD EXAMIANS APP
Magnetism and Electromagnetism The induced voltage across a coil with 250 turns that is located in a magnetic field that is changing at a rate of 8 Wb/s is 2,000 V 31.25 V 3,125 V 1,000 V 2,000 V 31.25 V 3,125 V 1,000 V ANSWER DOWNLOAD EXAMIANS APP
Magnetism and Electromagnetism A square cross-sectional magnet has a pole strength of 1 x 10 Wb and cross sectional area of 20 mm x 20 mm. What is the strength at a distance of 100 mm from the unit pole in air ? 63.38 N/Wb 633.8 N/Wb 63380 N/Wb 6338 N/Wb 63.38 N/Wb 633.8 N/Wb 63380 N/Wb 6338 N/Wb ANSWER DOWNLOAD EXAMIANS APP