Preserved fossil<span> (like a fossil in amber, ice or tar.</span>
Answer:
Ratio of magnetic field will be 
Explanation:
We have given radius of the loop r = 30 mm = 0.03 m
We know that magnetic field at the center of the loop is given by
---------eqn 1
Number of turns in the solenoid is given as n = 3 turn per mm = 3000 turn per meter
We know that magnetic field due to solenoid is given by
-------------eqn 2
Now dividing eqn 1 by eqn 2

<h2>
Time needed is 2545.45 seconds.</h2>
Explanation:
We know equation for power

Here we need to find time when for a 22 kW steam engine to do 5.6 × 10⁷ J of work.
So
Work = 5.6 × 10⁷ J
Power = 22 kW = 22 x 10³ W
Substituting

Time needed is 2545.45 seconds.