Answer to Question #55900 in Electricity and Magnetism for kola

Question

What is the self - inductance of an air-core solenoid, 1m long and 0.05m in diameter, if it has 1400 turns?
5.23mH
4.84mH
3.63mH
2.42mH

17 Which of the following is NOT correct?
A changing electric field can produce a changing magnetic field
A steady magnetic field produces a steady current
A changing magnetic field can produce a changing current
A changing magnetic field can produce a steady electric field

18 A rectangular coil of dimensions 20cm by 15cm lies with its plane parallel to a magnetic field of
0.5W/m2
. The coil, carrying a current of 10A experiences a torque of 4.5Nm in the field. How many loops has the coil?
100
60
30
20