Conservation of Energy and current

In summary, passing current through an infinite long wire with iron pieces nearby creates an electro-magnetic field and converts potential energy into kinetic energy. The negligible resistance wire allows for a large magnetic field with minimal energy loss, but the conservation of energy still applies due to the inductance of the wire. The addition of iron increases the inductance and thus the energy stored in the inductor.
  • #1
KronosZ
1
0
Assume there is a table with an infinite long wire passing through the centre and few iron pieces lying around the wire on the table. Now I pass current through the wire which creates electro magnetic field due to which all the iron particles get magnetic potential energy. They are attracted towards the electro magnet and potential energy gets converted into kinetic energy

Now let's assume negligible resistance wire so we can create extremely large magnetic field from small potential difference and loss of energy will be minimal.

So, how does the conservation of energy holds in this ? We are creating magnetic potential energy in iron pieces with minimal heat loss from current carrying wire(which is anyways independent of number of iron pieces)
 
Physics news on Phys.org
  • #2
Hi KronosZ, welcome to PF!
KronosZ said:
Now let's assume negligible resistance wire so we can create extremely large magnetic field from small potential difference and loss of energy will be minimal.
It doesn't work that way. Even with 0 resistance a wire has inductance and energy must be supplied or removed to change the magnetic field. This is well known and demonstrated in superconducting magnets like those used in MRI.
 
Last edited:
  • Like
Likes CWatters
  • #3
+1 to that.

The energy stored in an inductor is 0.5 L I2. Adding iron increases the inductance compared to the case without iron present.
 

What is conservation of energy?

Conservation of energy is a fundamental principle in physics stating that energy cannot be created or destroyed, only transformed from one form to another. This means that the total amount of energy in a closed system remains constant over time.

Why is conservation of energy important?

Conservation of energy is important because it helps us understand and predict how energy behaves in various systems. It allows us to calculate the amount of energy needed to perform a certain task and ensures that we are not wasting energy unnecessarily.

How is energy conserved in a circuit?

In a circuit, energy is conserved through the flow of electric current. The current is created by the movement of electrons, which carry energy from the source (such as a battery) to the load (such as a light bulb). The amount of energy remains constant throughout the circuit, with some energy being transformed into light or heat as it passes through the load.

What is the relationship between energy and current?

Energy and current are directly related in a circuit. The amount of current flowing through a circuit is directly proportional to the amount of energy being transferred. This means that the higher the current, the more energy is being used in the circuit.

How can we increase energy efficiency in current usage?

We can increase energy efficiency in current usage by using more energy-efficient devices, such as LED light bulbs. We can also reduce energy waste by turning off lights and electronics when not in use and by properly insulating buildings to reduce the need for heating and cooling. Additionally, using renewable energy sources can decrease our reliance on fossil fuels and reduce energy consumption.

Similar threads

A Relationship between magnetic potential and current density in Maxwell
    • Electromagnetism
Replies
2
Views
1K
I Current through U-wire (rail gun): Violation of (naive) conservation of momentum?
    • Electromagnetism
2
Replies
61
Views
2K
B Magnetic field produced by an electric current
    • Electromagnetism
Replies
5
Views
312
Conservation of Energy on Current-Carrying Wire in Magnetic Field
    • Electromagnetism
Replies
2
Views
827
I How Does a Magnetic Repulsion Machine Work?
    • Electromagnetism
Replies
5
Views
325
I Resulting magnetic field due to the passage of an AC current
    • Electromagnetism
Replies
27
Views
1K
I Question on Hall Effect and magnetic force
    • Electromagnetism
Replies
2
Views
864
I Work Done in Changing Shape of Current Carrying Loop
    • Electromagnetism
Replies
5
Views
864
I Explaining Current Behavior in an LC Circuit
    • Electromagnetism
Replies
6
Views
1K
I Magnetic field as result of length contraction
    • Electromagnetism
Replies
17
Views
1K

Hot Threads

Recent Insights

Back
Top