Physics  Electromagnetism
posted by Robert .
An inductor in the form of a solenoid contains 440 turns and is 15.8 cm in length. A uniform rate of decrease of current through the inductor of 0.421 A/s induces an emf of 175 µV. What is the radius of the solenoid?

Look up the formula for the inductance L of a solenoid. It is something like
L = mu* N^2 *A/l
W here l is the length and N is the number of turns. A is the cross sectional area. Mu is the permeability of free space
Use the induced emf for known current change rate to get the inductance.
V = L * dI/dT
Then use the solenoid formula to get the area A, which is pi*R^:2
Respond to this Question
Similar Questions

Physics repost
Suppose you wish to make a solenoid whose selfinductance is 1.2 mH. The inductor is to have a crosssectional area of 1.2 103 m2 and a length of 0.048 m. How many turns of wire are needed? 
physics induced voltage
A 500 turn solenoid with a length of 20 cm and a radius of 1.5 cm carries a current of 2.0 A. A second coil of four turns is wrapped tightly about this solenoid so that it can be considered to have the same radius as the solenoid. … 
physics induced voltage
A 500 turn solenoid with a length of 20 cm and a radius of 1.5 cm carries a current of 2.0 A. A second coil of four turns is wrapped tightly about this solenoid so that it can be considered to have the same radius as the solenoid. … 
tough physics question
A 500 turn solenoid with a length of 20 cm and a radius of 1.5 cm carries a current of 2.0 A. A second coil of four turns is wrapped tightly about this solenoid so that it can be considered to have the same radius as the solenoid. … 
Physics
An inductor is in the built in the shape of a solenoid of radius 0.20 cm, length 4.0 cm, with 1000 turns. This inductor is connected to a generator supplying an rms voltage of 1.2×〖10〗^(4) V AC at an angular frequency … 
Physics
The current in a 5.00mH inductor drops from 2.50A to zero in 5.ooms. What is the average emf induced in he inductor? 
Physics
Suppose you wish to make a solenoid whose selfinductance is 1.8 mH. The inductor is to have a crosssectional area of 1.60 103 m2 and a length of 0.049 m. How many turns of wire are needed? 
Physics
A circuit is composed of a capacitor C=2 μF, two resistors both with resistance R=11 Ohm, an inductor L=4.00e2 H, a switch S, and a battery V=5 V. The internal resistance of the battery can be ignored . Reminder: The "L=x.xxenn … 
Physics
A circuit is composed of a capacitor C= 3 micro F, two resistors both with resistance 69 Ohm, an inductor 6.00e2 H, a switch , and a battery 25 V. The internal resistance of the battery can be ignored . Reminder: The " L=x.xxenn H" … 
Physics
A circuit is composed of a capacitor C=3 μF, two resistors both with resistance R=69 Ohm, an inductor L=6.00e2 H, a switch S, and a battery V=25 V. The internal resistance of the battery can be ignored . Reminder: The "L=x.xxenn …