<span>BSL Physics Glossary - air resistance - definition. Translation: Air resistance is a force that is caused by air. The force acts in the opposite direction to an object moving through the air.</span><span>
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Answer:
Part a)

Part b)

Explanation:
Part a)
Electric potential is a scalar quantity
so here we can say that total potential due to a ring on its center is given as

here we know that



now we have


Part b)
Potential on the axis of the ring is given as



Oooooooooooooooooooooooooooooooooooo
Answer:
The current in the second wire is 4.4 A.
Explanation:
Given that,
Distance =7.0 cm
Current in first wire = 2.0 A
The magnetic field strength is zero at distance of 2.2 cm from the first wire.
We need to calculate the current in the second wire
Using formula of magnetic field




Here, 

Put the value into the formula


Hence, The current in the second wire is 4.4 A.