[Music] magnetic effects of electric current in 1820 Hans Christian AED one of the leading scientists accidentally discovered that a compass needle gets deflected when it is placed near a metallic conductor through which current is passing this observation demonstrated the connection between electricity and magnetism that means he played a crucial role in understanding electromagnetism ard's observation helped in the development of Technologies like radio television and fiber optics the unit of magnetic field strength is named as the Ed in his honor in this chapter we will learn about one the shapes and directions of the magnetic fields of a bar magnet two the magnetic effects of a stray lubed and coiled current carrying conductors and three the domestic electric circuits magnetic fields and lines place a bar magnet on a cardboard and sprinkle some iron filings on it now tap the cardboard gently we can observe that the iron filings arrange in a specific pattern do you know the reason for it magnets influence the space around them causing the iron filings to feel a force this Force arranges the iron filings in a specific pattern the area around the magnet where this force can be detected is called a magnetic field the lines formed by the alignment of iron filings represent magnetic field lines attraction and repulsions of a magnet when we place a compass close to a bar magnet the compass needle deflects the compass needle acts like a small magnet with its ends pointing North and South the end pointing North is called the North Pole and the end pointing South is called the South Pole we have observed that when two magnets have the same poles facing each other they push apart however when opposite poles face each other they attract and pull together drawing a magnetic field line with the help of a comp needle get a small compass and a bar magnet draw the outline of the magnet on the paper put the compass near the North Pole of the magnet notice that the South Pole of the compass needle points towards the North Pole of the magnet the North Pole of the compass points away from the magnet's North Pole Mark the positions of both ends of the needle move the compass needle to a new position so that its South Pole now occupies the spot where its North Pole was repeat this stepbystep process until you reach the South Pole of the magnet connect the marked points on the paper with a smooth curve this curve represents a magnetic field line repeat the processor to draw as many lines as you can magnetic field lines magnetic field has both Direction and magnitude the direction of the magnetic field field is where a North Pole of a compass needle points conventionally magnetic field lines emerge from North Pole and merge at this South Pole inside a magnet field lines go from South Pole to North Pole magnetic field lines form closed CES the closeness of field lines indicates the strength of the magnetic field stronger Fields have crowded field lines resulting in greater force on another magnets pole field lines lines don't cross because it would confuse the compass needle pointing in two directions at once so far we have studied the magnetic field of a permanent bar magnet now let us study the magnetic field of a straight current carrying conductor magnetic field of a stright current carrying conductor let us take a current carrying conductor a thick stright wire and pass it through a plain paper see that the paper is perpendicular to the wire connect the wire to a circuit and allow the current to pass through it now bring a magnetic compass near the conductor we can observe the deflection of compass needle this indicates that the electric current through the copper wire has produced a magnetic effect let us find out the shape of this magnetic field sprinkle some iron filings on the paper and tap it gently we can observe so that the iron filings get arranged in concentric circles this is the shape of the magnetic field and these are the magnetic field lines but how do we know the direction of this magnetic field place a magnetic compass on the magnetic field lines to know the direction of the magnetic field relation between the direction of the current flow and the direction of the magnetic field arrange the conductor and circuit as shown now place the magnetic compass below the conductor and allow the current to pass through it when the current flows from north to south Direction the compass needle deflects towards East now change the direction of current flow by changing the cell's Arrangement now the current flows from south to North and the needle deflects towards West that means if the direction of current flow changes the direction of the magnetic field also changes relation between the strength of magnetic field and the amount of current flow arrange the conductor and circuit as shown in this circuit we have a riat to increase and decrease the current flow in the circuit and an ameter to know the value of the current place a compass needle at some point say at Point p on the cardboard there is no deflection of the compass needle that means the magnetic field of the conductor is is not extend till here now increase the current by adjusting the rat now we can observe the needle in compass deflect means the magnitude of the magnetic field is increased with the increase in current flow it indicates that the magnitude of the magnetic field produced at a given point increases as the current Through the Wire increases right hand thumb rule the right hand thumb helps to determine the direction of magnetic fields of current current carrying conductors without a magnetic compass to know the direction of magnetic field Point your right thumb in the direction of the current curl your fingers around the conductor the direction in which your fingers curl represents the direction of the magnetic field lines around the conductor in this way using right hand thumb rule we can find out the direction of the magnetic field magnetic field in a circular conductor when we bend a straight wire into a circular Loop and pass a current through it the magnetic field lines around the loop form concentric circles these circles get larger as we move away from the loop at the center of the loop these circles appear as straight lines each point along the wire contributes to the straight magnetic field lines at the center using the right hand rule we can see that all sections of the wire contribute to the magnetic field lines in the same direction within the loop we can apply right hand thumb rule to know the direction of the magnetic field the side of the loop in which the flow of current is clockwise that side acts as South Pole and the side of the loop in which the flow of current is anticlockwise that side acts as North Pole we can remember this Direction with this technique if the flow is clockwise draw two arrows like this and join them then you will get yes which stands for South if the flow is anticlockwise draw two arrows like this and join them then you will get n which stands for north magnetic field of a coil when an electric current flows through a coil of wire it creates a magnetic field around the coil this magnetic field is stronger because there are more turns in the coil and it becomes even stronger if if the coil is wound into a tight spiral the strength of the magnetic field depends on factors such as amount of current flowing through the coil magnetic field due to a current in a solenoid a coil made of numerous circular turns of insulated copper wire closely wound in a cylinder shape is termed as solenoid the magnetic field lines around the current carrying solenoid are similar to a magnetic field lines of a bar magnet both exhibit similar behavior and appearance in a solenoid one end behaves like a magnetic north pole while the other acts as a South Pole inside the solenoid the magnetic field lines run parallel and straight this uniform Arrangement signifies that the magnetic field strength remains consistent at all points within the solenoid a robust magnetic field generated inside a solenoid can magnet ize magnetic materials like soft iron placed inside the coil the resulting magnet is known as an electromagnet force of a current carrying conductor in a magnetic field when an electric current flows through a conductor it creates a magnetic field around it this magnetic field can exert a force on a nearby magnet to determine the direction of this Force we use Fleming's left hand rule according to this rule if if you stretch out your left hand thumb four finger and middle finger perpendicular to each other your four finger points the direction of the magnetic field your middle finger points the direction of the current and your thumb then indicates the direction of the force acting on the conductor devices utilizing this interaction between the current carrying conductors and magnetic fields include electric motors generators loud speakers micro phones and various measuring instruments domestic electric circuits electricity is supplied to our homes through the mains the mains consist of two wires the Live Wire that is positive usually covered in red insulation and the neutral wire negative typically insulated in Black in our country the potential difference between the two wires is 220 Vol that means the voltage of electric current of our homes is 2 20 OLS at the meter board in the house the main wires pass through an electric meter and a main fuse before connecting to the line wires inside the house the line wires Supply electricity to separate circuits within the house usually we have two different circuits in our house one rated as 5 amps for devices such as bulbs and fans and other rated as 15 amps for high power appliances like gysers Etc the Earth wire insulated in green is connected to a metal plate buried near the house one of the primary purpose of this Earth wire is to provide a safe path for electrical currents in case of a fault if there is a short circuit or some other Mal functioning that causes the metal casing of an appliance or electrical device to become live with electricity then the Earth wire provides a low resistance path for the current to flow into the ground preventing the electric shock to humans and animals the Earth wire helps protect electrical equipment and appliances from damage by providing a path for excess electrical current to safely dissipate into the ground this can help prevent damage from Power surges or lightning strikes appliances are connected across the live and neutral wires within each separate circuit with individual switches to control the flow of current to ensure each Appliance receives an equal potential difference they are connected in parallel an electrical fuse is a safety device designed to protect electrical circuits and equipment from damage caused by excessive currents that is overloading overloading can occur due to damaged insulation or Appliance faults it results in a sudden increase in current known as short circuiting overloading can also result from a spike in Supply voltage or by connecting too many appliances to a single socket how does a fuse Works fuse consists of a thin strip or wire made of a material that melts easily such as copper or silver it enclosed in a protective casing when the current passing through the fuse exceeds a certain level the wire heats up and melts this breaks the circuit and disconnect the power supply this is all about the magnetic effects of electric current thanks for watching please like the video please share this video with your friends please subscribe to Great booster Channel press the Bell icon to get all the latest updates check the description to find Links of other useful videos check the end screens for our new [Music] videos