The bar magnet and the electromagnet act identical. The difference being a electromagnet is a coil of wire that has a power source connect to both ends, this energizes the coil with an electromagnetic field.
Answer:
b.only when the current in the first coil changes.
Explanation:
An induced current flow in the second coil only when there is a change in current in the first cool. A steady current will produce no change in flux (due to magnetic effect of a current) by the first coil, and according to Faraday, induced current is only produced when there is a change in flux linkage.
Answer
given,
force per unit length = 350 µN/m
current, I = 22.5 A
y = y = 0.420 m



I₂ = 32.67 A
distance where the magnetic field is zero


there the distance at which the magnetic field is zero in the two wire is at 0.248 m.
The amount of diffraction depends on the wavelength of light, with shorter wavelengths being diffracted at a greater angle than longer ones (in effect, blue and violet<span> light are diffracted at a larger angle than is red light).
I hope my answer has come to your help. God bless and have a nice day ahead!
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A heat engine would be less efficient due to many factors
For instance, a heat engine is more efficient when it uses in cold weather because there is a greater temperature difference ( Carnot Efficient )
A heat engine could be less efficient because of friction
Hope it helps I am a beginner