Motors contain electromagnets which transform

Motors are used in a wide range of applications, such as fans, power tools, appliances , electric vehicles , and hybrid cars. Motors have many different working parts in order for them to continually rotate, providing power as needed. Motors can run off of direct current DC or alternating current AC , and both have their benefits and drawbacks. For the purpose of this article a DC motor will be analyzed, to read about AC motors, click here.

The main parts of a DC motor include: [3]. For the second half of the rotation, though, electricity enters through the red half of the commutator, causing current to flow into and through the armature in the opposite direction.

This constant reversal essentially turns the battery's DC power supply into alternating current, allowing the armature to experience torque in the right direction at the right time to keep it spinning.

View an animated video about DC motors. Interactive Tutorials. Changes were made to the original material, including updates to art, structure, and other content updates.

Skip to Content Go to accessibility page. Physics My highlights. Table of contents. Chapter Review. Test Prep. By the end of this section, you will be able to do the following: Explain how electric motors, generators, and transformers work Explain how commercial electric power is produced, transmitted, and distributed.

Teacher Support The learning objectives in this section will help your students master the following standards: 5 The student knows the nature of forces in the physical world. The student is expected to: G investigate and describe the relationship between electric and magnetic fields in applications such as generators, motors, and transformers.

A vertical loop of wire in a horizontal magnetic field is attached to a vertical shaft. When current is passed through the wire loop, torque is exerted on it, making it turn the shaft. The magnetic field generates a force F on each vertical segment of the wire loop, which generates a torque on the shaft. Notice that the currents I in and I out I in and I out have the same magnitude because they both represent the current flowing in the wire loop, but I in I in flows into the page and I out I out flows out of the page.

The graph gives the emf of the generator as a function of time. Generator Click to view content. The steam produced by burning coal impacts the turbine blades, turning the shaft which is connected to the generator. On the right is a toroidal transformer, which is smaller than the laminated-core transformer for the same power rating but is more expensive to make because of the equipment required to wind the wires in the doughnut shape.

The magnetic field created by the primary coil is mostly confined to and increased by the core, which transmits it to the secondary coil. Any change in current in the primary coil induces a current in the secondary coil. Magnetic Rope Memory To send men to the moon, the Apollo program had to design an onboard computer system that would be robust, consume little power, and be small enough to fit onboard the spacecraft.

If the bit wire were looped twice around each core, how would the voltage induced in the bit wire be affected? Electric power is usually generated at greater than 10 kV, and transmitted long distances at voltages ranging from kV to kV to limit energy losses.

Local power distribution to neighborhoods or industries goes through a substation and is sent short distances at voltages ranging from 5 to 13 kV. This is reduced to , , or V for safety at the individual user site. What is an electric motor? What happens to the torque provided by an electric motor if you double the number of coils in the motor? What is a step-up transformer?

The ratio is five times. The ratio is 10 times. The ratio is 15 times. The ratio is 20 times. Previous Next. A simple electric motor. Use the highlighted words in the text to find out how it works. The motor is connected to a battery. When the switch is closed, the current starts to flow and the coil becomes an electromagnet.

In this case the current is flowing anticlockwise in the top of the coil. This makes the top a north pole. This north pole is attracted to the south pole on the left. So the top of the coil turns towards the left. Notice that the bottom of the coil is a south pole and is attracted to the magnet on the right. Question 1. Look at the descriptions below.