Hello there!
For this:
1). Convert 10km to meters!
2). Convert the 30 minutes into seconds!
3). Use the following formula to solve for speed!
speed= distance/time
Note: The units should automatically work out to m/s. :)
My goal is to make sure you understand the problem, which is why I won't be giving you the answer. It'll be more work now, but less work in the future! :)
Hope this helped!
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Answer:
55407
Explanation:
we have given that magnetic field B=3.5 T
current through the coil=90 A
Length of solenoid =0.72 m
we know the formula of magnetic field

so 
so the number of turn in solenoid will be 55407
Answer:
Ruko zara kuch Time dedo na please