Question

As you have learned, an electromagnet is a magnet that is produced by electric current. Think about how electromagnets are used and what you have seen or heard of them being used for. In your initial discussion post, respond to the following: (Please answer ALL questions!)  

• Which of the principles or laws discussed in this module explain how an electromagnet works?
• Describe in detail two modern applications of electromagnets. Do these electromagnets draw a large amount of current or a little? How do you know? What supplies that current?
• Why do you think electromagnets are used in these different ways?
• What is the advantage of using an electromagnet rather than a permanent magnet?

I will be giving you a thumbs up if all questions are answered!

Answer 1

1. An electromagnet works because an electric current produces a magnetic field. The Biot-Savart Law can be used to determine the magnetic field strength from a current segment. For the simple case of an infinite straight current-carrying wire it is reduced to the form B=μ0I / 2πr.A more fundamental law than the Biot-Savart law is Ampere ‘s Law, which relates magnetic field and current in a general way. It is written in integral form as ∮B⋅dl=μ0* Ienc ,where I_enc is the enclosed current and μ₀ is a constant.

2. We can find enormous practical application of electromagnetism in everyday life from domestic appliances to research applications.

In domestic applications we can observe the phenomena in lighting, heating and kitchen appliances , in communication systems this exist in all telecommunication equipments and communication networks , in industrial systems this can be applied in motors, generators, sensor and actuator devices, etc.
For domestic applications , Current is generally supplied by the power lines we use in homes. Electromagnets draw small amounts of current in the order of 1-10 Amps.

3. Electromagnets basically convert energy of the current into magnetic energy which can be used to produce heat, light, force etc, hence the different applications.

4. Electromagnets are beneficial because,
1.Magnitude of currents can be varied resulting in many different applications.
2.Polarity of current can be varied resulting in change in direction of field which can have different applications.