Current Electricity and Nuclear Physics Fundamentals
Current Electricity: Chapters 21, 22, and 23
Key Definitions and SI Units
- Electric Current (A): The rate of flow of charge.
- Electric Power (W): The rate of energy dissipation.
- Electric Charge (C): The amount of energy or electrons transferable through methods like friction, induction, or conduction.
- Potential Difference (V): The energy per unit charge that causes current to flow; also known as voltage.
- Electrical Resistance (Ω): The opposition to the flow of current from a voltage source.
- Electrical Energy (J): Energy stored in the voltage source.
Functions of Circuit Components
- Ammeter: Measures the current flowing in a device or circuit.
- Voltmeter: Measures the voltage in a circuit or device.
- Diodes: Allow current to flow in only one direction.
- Variable Resistors: Used to change the current in a circuit.
- Buzzer: Converts electrical energy into sound energy.
- Capacitors: Store energy in a circuit.
- Battery: Converts chemical energy into electrical energy.
- Fuse: A safety device that breaks the circuit if the current exceeds a safe level.
- Lamps: Indicate whether electricity is flowing.
- Resistors: Control the flow of current to other components.
Series and Parallel Circuits
An ammeter is connected in series, where the current has only one path to flow. A voltmeter is connected in parallel, where the current has multiple paths.
Nuclear Physics: Chapter 30
Key Definitions
- Fission: The splitting of a heavy, unstable nucleus into two lighter, stable nuclei, releasing energy.
- Fusion: The joining of two light, unstable nuclei to form a heavier, stable nucleus, releasing energy.
- Strong Nuclear Force: The force that overcomes the repulsive electric force between protons within the nucleus.
- Electric Force: The force that tends to push protons apart.
- Isotopes: Atoms of the same element with the same number of protons but different numbers of neutrons.
- Nuclear Decay: The process where a massive nucleus splits into smaller nuclei, releasing energy. This occurs when an atom of one element emits charged particles and transforms into a different element.
Properties of Ionizing Radiations
Alpha Particles: Positively charged, can conduct electricity, have the highest ionization ability, are weakly deflected in magnetic/electric fields, and have the shortest range in air.
- Beta Particles: Negatively charged, strongly ionize gases, and are strongly deflected in magnetic/electric fields.
- Gamma Rays: Have no charge, are the least ionizing, are not deflected in magnetic/electric fields, and are the most penetrating (wave-like).
Nuclear Fission in a Nuclear Reactor
The heat energy produced by nuclear fission is used to convert water into steam. The steam then spins turbines within a magnetic field in a generator, producing electricity.
Nuclear Fusion in the Sun
Nuclear fusion occurs in the sun, releasing energy and light. Hydrogen atoms combine to form helium atoms, releasing tremendous amounts of energy.