Wednesday, 25 May 2016

Day 1 reflection

Today was our first day at NTU. It was big, huge and yes..... AMAZING. The students studying area, labs and architecture were really good. We then met our professor, Mr. Leng. He was a very friendly person who was open to all sorts of question and he let us do whatever we wanted and we could experiment with the materials given. He made difficult concepts look easy and he even called some students to assist him and we all soon became friends. Mr. Leng taught us about how a D.C. motor works and about the fleming left-hand rule.

FLEMING'S LEFT-HAND RULE

Fleming's left-hand rule consists of three fingers

  • Thumb
  • Index finger
  • Middle finger
The Thumb represents the direction of the force, the Index finger represents the magnetic field and the middle finger represents the Current flowing through the wire
D.C. Motor(Direct current)

A D.C. motor consists of some parts mainly
  • A battery
  • A magnet
  • A coil of copper wire
  • Two metallic stands
The battery powers the motor while the magnet provides the ‘kick' that is needed to turn the coil of wire. If you were to zoom into the copper wire, you would find out that the coil of wire is half-insulated. This allows the coil of wire to make half a turn before inertia kicks in and allows the coil of wire to make a complete turn. 
















Tuesday, 17 May 2016

What is a DC Motor????

A DC motor is any of a class of electrical machines that converts direct current electrical power into mechanical power. The most common types rely on the forces produced by magnetic fields. Nearly all types of DC motors have some internal mechanism, either electromechanical or electronic, to periodically change the direction of current flow in part of the motor. Most types produce rotary motion; a linear motor directly produces force and motion in a straight line.
DC motors were the first type widely used, since they could be powered from existing direct-current lighting power distribution systems. A DC motor's speed can be controlled over a wide range, using either a variable supply voltage or by changing the strength of current in its field windings. Small DC motors are used in tools, toys, and appliances. The universal motor can operate on direct current but is a lightweight motor used for portable power tools and appliances. Larger DC motors are used in propulsion of electric vehicles, elevator and hoists, or in drives for steel rolling mills. The advent of power electronics has made replacement of DC motors with AC motors possible in many applications.(wikipedia, 2016)