Answer:Increase by a factor of 25
Explanation:
We know that magnetic force is proportional to
where r is the distance between them
Thus
Where =magnetic field
If distance is reduced by a factor of then force must increase by a factor of
because
so
The efficiency of the process is 42%
From the question given above, the following data were obtained:
Useful energy = 250 watt
Wasteful energy = 600 watt
<h3>Efficiency =? </h3>The efficiency of the process can be obtained as illustrated below:
Therefore, the efficiency of the process is 42%
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