FreeNotes
Household electricity can present several hazards, including: Electric Shock: When a person comes into direct contact with an electrical source, it can lead to an electric shock, which can cause burns, muscle spasms, or even be fatal in severe cases. Electrical Fires: Faulty wiring, overloading circuits, or electrical appliances with malfunctioning components can overheat and … Read more
Short Circuit and Open Circuit: Short Circuit: A short circuit occurs when the live wire (also known as the hot wire) comes into direct contact with the neutral wire, or any other conducting material, bypassing the load (such as an appliance or light). This leads to a low-resistance path for the current to flow, which … Read more
Electricity is supplied to houses through a well-organized system that involves multiple steps, from generation to distribution. Here’s how it works: 1. Generation of Electricity: Power Stations: Electricity is generated at power stations (such as coal, hydroelectric, nuclear, or renewable energy plants). These plants convert energy sources (like coal, water, or solar energy) into electrical … Read more
A galvanometer, ammeter, and voltmeter are all types of instruments used to measure electrical quantities in a circuit. Each has a specific function and is connected in a unique way to the circuit. 1. Galvanometer: Function: A galvanometer is used to detect and measure small amounts of current in a circuit. It can also be … Read more
Difference Between Direct Current (DC) and Alternating Current (AC) Parameter Direct Current (DC) Alternating Current (AC) Direction Flows in one constant direction. Changes direction periodically. Waveform A constant, unidirectional flow of current. The current alternates between positive and negative cycles, forming a sinusoidal (or other periodic) waveform. Voltage Constant voltage. Voltage alternates between positive and … Read more
Kilowatt-Hour (kWh) A kilowatt-hour (kWh) is a unit of energy that is commonly used to measure electrical energy consumption. It represents the amount of energy consumed by a device with a power rating of 1 kilowatt (kW) operating for 1 hour. In simpler terms, 1 kWh is the energy used when a 1,000-watt device runs … Read more
Electric Power is the rate at which electrical energy is converted into other forms of energy, such as heat, light, or mechanical energy, in an electrical circuit. The unit of electric power is the watt (W), and it is often used to express the rate at which energy is consumed or produced in electrical devices, … Read more
Joule’s Law of Heating Joule’s Law of Heating states that the amount of heat Q produced by a current passing through a conductor is directly proportional to: The square of the current (I2), The resistance of the conductor (R), The time (t) for which the current flows. Mathematically, Joule’s Law is expressed as: Q=I2Rt Where: … Read more
The brightness of a bulb is determined by the power it dissipates, which depends on the current passing through it and the voltage across it. Power P dissipated by a resistor (or bulb) is given by the formula: P=V2/R or alternatively, in terms of current I: P=I2R where: P is the power dissipated (which determines … Read more
Resistors in Parallel When resistors are connected in parallel, they are arranged such that the opposite ends of each resistor are connected to the same two points in the circuit. In other words, they share the same potential difference (voltage) across them. Characteristics of Resistors in Parallel: Same Voltage: All resistors in parallel experience the … Read more