If the radius of a circular loop carrying current is halved, how does the magnetic field at the center change?
Practice Questions
1 question
Q1
If the radius of a circular loop carrying current is halved, how does the magnetic field at the center change?
Remains the same
Doubles
Halves
Quadruples
The magnetic field at the center is inversely proportional to the radius, so it quadruples.
Questions & Step-by-step Solutions
1 item
Q
Q: If the radius of a circular loop carrying current is halved, how does the magnetic field at the center change?
Solution: The magnetic field at the center is inversely proportional to the radius, so it quadruples.
Steps: 7
Step 1: Understand that a circular loop carrying current creates a magnetic field at its center.
Step 2: Know that the strength of the magnetic field (B) at the center of the loop is related to the radius (r) of the loop.
Step 3: Remember the formula for the magnetic field at the center of a circular loop: B = (μ₀ * I) / (2 * r), where μ₀ is a constant and I is the current.
Step 4: Notice that in this formula, the radius (r) is in the denominator, which means that as the radius decreases, the magnetic field increases.
Step 5: If the radius is halved (r becomes r/2), substitute this into the formula: B = (μ₀ * I) / (2 * (r/2)) = (μ₀ * I) / (r) = 2 * (μ₀ * I) / (2 * r).
Step 6: This shows that the magnetic field at the center becomes 2 times stronger when the radius is halved.
Step 7: Since the magnetic field is inversely proportional to the radius, halving the radius results in quadrupling the magnetic field strength.