The current in an inductor when energy is stored. Please help

In summary, the current in a 15mH inductor is approximately 0.07A when the stored energy is 42μJ. This is determined using the equation E = 1/2 L i^2 and rounding to two significant figures.
  • #1
BryceHarper
15
0
The current in an inductor when energy is stored. Please help!

Homework Statement



What's the current in a 15mH inductor when the stored energy is 42μJ

Homework Equations



E = 1/2 L i^2

The Attempt at a Solution



.000042J = (.5)(.015H)(i^2)
.000042J = (.0075)(i^2)
.0056 = i^2
√ (.0056) = i
.0748331 = i

I need to put the answer in with only two sig figs so i put in .07 but it was wrong :grumpy:
What am I doing wrong?
 
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  • #2
Hi BryceHarper! :smile:
BryceHarper said:
I need to put the answer in with only two sig figs so i put in .07 but it was wrong :grumpy:

.07 is two decimal places but only one significant figure :wink:
 
  • #3


I'm dumb haha. Thanks!
 

1. What is an inductor?

An inductor is an electrical component that is used to store and release energy in the form of a magnetic field. It is typically made up of a coil of wire and is commonly used in electronic circuits.

2. How does an inductor store energy?

When current flows through the coil of an inductor, a magnetic field is created. This magnetic field stores energy in the form of potential energy. The strength of the magnetic field is directly proportional to the amount of current flowing through the inductor.

3. What happens to the current in an inductor when energy is stored?

When energy is stored in an inductor, the current in the circuit decreases. This is because the inductor resists changes in current, causing it to act as a temporary energy storage device.

4. How is the energy released from an inductor?

The energy stored in an inductor is released when the current in the circuit is disrupted or when the power supply is turned off. When this happens, the magnetic field collapses and the inductor releases its stored energy in the form of a current spike.

5. What are some applications of inductors?

Inductors are commonly used in electronic circuits for various purposes, such as smoothing out power supply ripple, filtering out unwanted signals, and creating oscillating circuits. They are also used in power supplies, motors, and transformers.

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