C) alternating current .
<span>
B)direct current </span>
All you would do is for a, 10 times 2 is 20 so it would be 20-dB
For b, 10 times 4 is 40 so it would be 40-dB
<span>For c, 10 times 8 is 80 so it would be 80-dB</span>
<h3><u>Answer;</u></h3>
- A moving electric charge creates a magnetic field at all points in the surrounding region.
- An electric current in a conductor creates a magnetic field at all points in the surrounding region.
- A permanent magnet creates a magnetic field at all points in the surrounding region.
<h3><u>Explanation;</u></h3>
- A magnetic field can be created by running electricity through a wire. All magnetic fields are created by moving charged particles. it is important to also note that charged particles create magnetic fields only when they are moving.
- The strength of the magnetic field generated or created is proportional to the amount of current flowing through the wire. Thus, increasing the current increases the strength of the magnetic field.
Answer:
B = 0.75 T
Explanation:
As we know that the force on a moving charge in magnetic field is given by the formula

here we have

here we know that



now from above equation we have

