A Rowland ring measures the charge that passes through a sense coil by integrati
ID: 1263433 • Letter: A
Question
A Rowland ring measures the charge that passes through a sense coil by integrating the current in the sense coil over time, as shown in the diagram below. Both the sense coil and the primary coil are wrapped tightly around the material. These coils have area A, and the number of turns in the sense coil is N. It can be shown, where Q is the charge measured in the sense coil, that the change in magnetic field in the material is given by; dB = -QR/NA A sense coil with a resistance of 0. 375 ohm is wrapped tightly in 10 turns around a magnetic material of area 0. 240 m^2. When a switch is closed in the primary coil, a charge of 0.600 mC is measured in the sense coil. If the magnetic field was initially zero, what is the magnitude of the new magnetic field in the material?Explanation / Answer
apply the magentic field dB = QR/NA
where chargeQ = 0.6 e-3 C
R is resisatcne = 0.375 ohms
N = no. of turns = 10
A = 0.24 m^2
so
dB = 0.6 e-3 * 0.375/(10 * 0.24)
dB = 9.375 *10^-5 tesla ---------<<<<<<<Answer