If you're seeing this message, it means we're having trouble loading external resources on our website. If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked. In this section, we shall learn about the transfer of charge by induction using a negatively charged object. Let us consider two metal spheres A and B touching each other, as shown in the figure. Let us take a negatively charged rubber balloon. If we bring the charged balloon near the spheres, electrons within the two-sphere system will be induced to move away from the balloon due to the repulsion between the electrons of the balloon and the spheres. Subsequently, the electrons from sphere A get transferred to sphere B.The migration of electrons causes sphere A to become positively charged and sphere B to be negatively charged. The overall two-sphere system is hence electrically neutral. The spheres are then separated using an insulating cover such as gloves or a stand as shown in the figure (avoiding direct contact with the metal). When we remove the balloon, the charge gets redistributed, spreading throughout the spheres, as shown in the figure.
In this section, we shall learn about the transfer of charge through the process of induction using a positively charged object. Taking two spheres A and B, touching each other, as shown in the figure, if we bring a positively charged balloon near sphere A, the electrons from sphere B migrate towards sphere A due to the attraction between opposite charges, thus leaving the sphere B deficit of electrons. As a result, sphere A is negatively charged and sphere B is positively charged. The spheres are then separated using an insulating cover, a stand or gloves. When the balloon is removed, the charges in spheres A and B redistribute, spreading out evenly.
An electroscope is an instrument that is used to detect the presence and magnitude of electric charges on a body. An electroscope is commonly used by physics teachers to demonstrate the electrostatic principles of charging and charge interactions. The demonstration of the induction process of charging is commonly performed with an electroscope. In this demonstration, a charged particle is brought close to but not touching the electroscope. The electrons in the electroscope are induced to move due to the presence of the charged particle above the plate of the electroscope. With the charged particle still held above the plate, the electroscope is touched. At this point, electrons will flow between the electroscope and the ground, giving the electroscope an overall charge. The needle of the electroscope deflects indicating an overall charge when the charged particle is pulled away from it. From this demonstration, the following fundamental principles can be summarised:
The application of inductive charging can be divided into high power and low power categories. The low-power applications generally include handheld devices, phones, computers and other devices which charge at power levels below 100 watts. High power inductive charging applications include charging batteries of power levels above 1 kilowatt. The most prominent application is the charging of electric vehicles where automated and wireless inductive charging is provided as an alternative to plug-in charging.
An electroscope is used to detect the nature of the charge.
The charging by induction method is used in charging microphones, smartphones, etc. As induction method is the transfer of charge from one object to another so by placing the phone on the dock charge transfer from dock to phone. To learn more about charging by induction and other related topics, download BYJU’S – The Learning App. |