Biot-Savart Law and its Application to Current Carrying Circular Loop NEET Questions

Physics - Magnetic Effects of Current and Magnetism

Biot-Savart Law and its Application to Current Carrying Circular Loop MCQ Questions


13.
A current of 2 A flows in a circular coil of radius 5 cm having 50 turns. The magnetic field at its centre is:
A.
1.256 × 10⁻³ T
B.
2.5 × 10⁻³ T
C.
12.56 × 10⁻⁴ T
D.
6.28 × 10⁻⁴ T
😑 View Answer Rough Work Error
ANSWER :
A. 1.256 × 10⁻³ T
14.
Two concentric circular coils of radii r and 2r carry equal currents in opposite directions. The magnetic field at the common centre is:
A.
3μ₀I / (4r)
B.
μ₀I / (4r) in the direction of smaller coil's field
C.
μ₀I / (2r) in the direction of larger coil's field
D.
Zero
😑 View Answer Rough Work Error
ANSWER :
B. μ₀I / (4r) in the direction of smaller coil's field
15.
The magnetic field at the centre of a circular coil of n turns carrying current I and radius r is directly proportional to:
A.
n/I
B.
nI
C.
r²
D.
I/r²
😑 View Answer Rough Work Error
ANSWER :
B. nI
16.
A wire of length L carrying current I is bent into a circular loop. The magnetic field at its centre is B₁. If the same wire is bent to form a circular loop of two turns, the field at centre becomes B₂. The ratio B₂/B₁ is:
A.
1/4
B.
4
C.
2
D.
1/2
😑 View Answer Rough Work Error
ANSWER :
B. 4
17.
The magnetic field due to a straight current-carrying conductor of finite length at a point is determined using:
A.
Coulomb's law
B.
Faraday's law
C.
Biot-Savart law
D.
Gauss's law
😑 View Answer Rough Work Error
ANSWER :
C. Biot-Savart law
18.
The magnetic field at a point on the axis of a current loop far away from the centre (x >> R) varies as:
A.
1/x³
B.
1/x
C.
1/x²
D.
1/x⁴
😑 View Answer Rough Work Error
ANSWER :
A. 1/x³