Dc motor 10th class physics chapter 15 | DC Motor working in urdu hindi | atif Ahmad Official скачать в хорошем качестве

Dc motor 10th class physics chapter 15 | DC Motor working in urdu hindi | atif Ahmad Official

Dc motor 10th class physics chapter 15 | DC Motor working in urdu hindi | atif Ahmad Official 15.4 D. C. MOTOR We can see from Fig. 15.9 that the simple coil placed in a magnet cannot rotate more than 90°. The forces push the PQ side of the coil up and the RS side of the loop down until the loop reaches the vertical position. In this situation, plane of the loop is perpendicular to the magnetic field and the net force on the coil is zero. So the loop will not continue to turn because the forces are still up and down and hence balanced. Fig. 15.9: Working principle of D.C motor How can we make this coil to rotate continuously? It can be done by reversing the direction of the current just as the coil reaches its vertical position. This reversal of current will allow the coil to rotate continuously. To reverse direction of current, the connection to coil is made through an arrangement of brushes and a ring that is split into two halves, called a split ring commutator (Fig. 15.9). Brushes, which are usually pieces of graphite, make contact with the commutator and allow current to flow into the loop. As the loop rotates, so does the commutator. The split ring is arranged so that each half of the commutator changes brushes just as the coil reaches the vertical position. Changing brushes reverse the current in the loop. As a result, the direction of the force on each side of the coil is reversed and it continues to rotate. This process repeats at each half-turn, causing coil to rotate in the magnetic field continuously. The result is Related searches 1. 10th class physics chapter 15 DC motor 2. DC motor 10th class physics 3. Dc motor in urdu hindi