Answer:
changing the magnetic field more rapidly
Explanation:
According to Faraday's law, whenever there is a change in the magnetic lines of force, it leads the production of induced emf. The magnitude of induced emf is proportional to to the rate of change of flux.
Hence if the magnetic field inside a loop of wire is changed rapidly, the magnitude of induced emf increases in accordance with Faraday's law of electromagnetic induction stated above when the magnetic field is changed more rapidly, hence the answer.
When your head sticks out of the water the upthrust reduces as your head is no longer displacing water, and there is 0 resultant force so you float at that level. hope this helps, can i get brainliest please
- The length of its image =

Given,
length of object, 
We know, for flat refracting surface,
Image distance = object distance
So,
magnification is = 
length of the image,

Here, negative sign means inverted image.
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