Q27.A long straight wire of radius ' a ' caries a steady current i. The current is uniformly distributed across its cross section. The ratio of the magnetic field at a and 2a is 2 (1) 1 (2) 4 4 (3) 1 (4) 12
What This Question Tests
This question requires applying Ampere's law to calculate the magnetic field both inside and outside a long straight wire with uniform current distribution and finding their ratio.
Concepts Tested
Formulas Used
B_inside = (μ₀Ir)/(2πa²)
B_outside = (μ₀I)/(2πr)
📚 NCERT Sections This Tests
4.6 — A 3.0 Cm Wire Carrying A Current Of 10 A Is Placed Inside A Solenoid
Physics Class 11 · Chapter 4
4.6 A 3.0 cm wire carrying a current of 10 A is placed inside a solenoid perpendicular to its axis. The magnetic field inside the solenoid is given to be 0.27 T. What is the magnetic force on the wire?
4.4 — A Horizontal Overhead Power Line Carries A Current Of 90 A In East To
Physics Class 11 · Chapter 4
4.4 A horizontal overhead power line carries a current of 90 A in east to west direction. What is the magnitude and direction of the magnetic field due to the current 1.5 m below the line?
4.7 — Two Long And Parallel Straight Wires A And B Carrying Currents Of
Physics Class 11 · Chapter 4
4.7 Two long and parallel straight wires A and B carrying currents of 8.0 A and 5.0 A in the same direction are separated by a distance of 4.0 cm. Estimate the force on a 10 cm section of wire A.
📋 Question Details
- Chapter
- Magnetic Effects of Current
- Topic
- Magnetic field of a long straight wire
- Year
- 2007
- Shift
- Unknown
- Q Number
- Q27
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 4: Moving Charges and Magnetism
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