Inductors Practice Problems

A 260 mH inductor is connected to a circuit, as shown. The change in current in the circuit, di/dt = constant. A voltmeter connected across points p and q reads 2.02 V, q lying on at lower potential. Does the current in the circuit rise or fall?

The following measurements were obtained from a toroid during specification testing. An induced emf of magnitude 13.5 mV is observed when the current changes at a rate of 0.0322 A/s. In a different test, the mean flux per turn in the solenoid is 0.00372 Wb when the current in the solenoid is 2.60 A. Determine the total number of turns in the solenoid.

The diameter of a toroid is 22 cm. It has a cross-sectional area of 0.500 cm². Determine the number of turns required to make the inductance of the toroid 0.200 mH.  

Analysis shows that the current across a 15 mH induction coil changes from 180 mA to 80 mA in a duration of 20 μs. Calculate the potential difference across the inductor, and specify if the potential difference increases or decreases in the direction of the current.

You are provided with a graph of the potential difference against time below for a 15 mH inductor. If the current at t = 0 ms is 0.80 A, calculate the current when t = 8 ms.

The electric current flowing through an induction coil will obey the equation I = I₀e^-tL/R. Determine what the equation will be when it obeys the conditions of the voltage across the inductor.

An inductive coil experiences a current given by I = I₀e ^{- (tR / L)}. Calculate the potential difference across the coil for L = 16 mH, I₀ = 30 mA, and R = 20 Ω at i) t = 0 ms and ii) t = 4.0 ms.

A 10 cm long solenoid used in an electromagnet has a radius of 1.25 cm. Calculate the stored energy when 160 turns of wire transmit 0.60 A of electric current.

Some applications, such as containing hot plasma for scientific research, require powerful magnetic fields. A solenoid of radius 15.0 cm and length 70.0 cm conducts a current of 120 A, creating a magnetic field of strength 6.00 T inside the solenoid. Calculate the energy stored in the magnetic field, assuming an ideal solenoid with an even magnetic field inside and zero magnetic fields outside the solenoid.

Consider estimating the total energy that is stored in the magnetic field of Jupiter but only within the first 10.0 km above its surface. The magnetic field strength averages approximately 4.17 x 10⁻⁴ T.