Physics 10

How is electricity supplied to houses by the electricity department? How do we distribute it in household circuits?

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

What is the function of a galvanometer, ammeter, and voltmeter? How are they connected in circuits?

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

12. Differentiate between direct current (DC) and alternating current (AC). Define the following terms for AC: (i) Cycle, (ii) Time period, (iii) Frequency.

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

Define kilowatt-hour (kWh). What is its relation with joule? How can you calculate energy in kWh by a formula?

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

In a circuit, three bulbs are connected in series and in another circuit, three bulbs are connected in parallel. The magnitude of the emf source for both circuits is the same. How can you explain the difference in brightness of bulbs in both circuits?

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

How are resistances connected in parallel? What are their characteristics? Derive the formula for equivalent resistance.

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

How are resistances connected in series? What are their characteristics? Derive the formula for equivalent resistance.

Resistances in Series Connection When resistors are connected end-to-end in a single path for the flow of current, they are said to be in series. In this type of connection, the current remains the same through all the resistors, but the voltage divides among them. Characteristics of Series Resistance Connection Same Current: The same current … Read more

Define resistance and its unit. What is the cause of resistance? On what factors does the resistance of a metallic conductor depend?

Definition of Resistance Resistance (RRR) is the opposition offered by a material to the flow of electric current. It determines how much a conductor resists the movement of free electrons when a voltage is applied. Mathematically, resistance is given by Ohm’s Law: R=V/I​ where: R = Resistance (Ohms, Ω) V = Voltage (Volts, V) I = … Read more