Senior High School General Science Core Subject Study Guide

LESSON EXEMPLAR STRUCTURE AND GUIDELINES

• Core Purpose: The Senior High School Lesson Exemplar (LE) is designed to assist teachers in delivering curriculum content and standards while ensuring meaningful, engaging instruction through constructive alignment of standards, experiences, and assessments.

• SHS Instructional Design Framework (SHSIDF): The LE is anchored in this framework to prepare learners for higher education, employment, and entrepreneurship.

• AID Instructional Flow:

  • Activating Prior Knowledge: Connects existing knowledge to new concepts and clarifies learning goals and real-life applications.

  • Instituting New Knowledge: Focuses on concept mastery through guided exploration, explicit instruction, and collaborative activities.

  • Demonstrating Knowledge and Skills: Provides opportunities for application, synthesis, and remediation or enrichment.

• Program Integrations:

  • Integrative Performance Tasks (IPT): Interdisciplinary assessments woven into instruction rather than isolated end-of-term projects.

  • EdTech Integration: Incorporates educational technologies to foster creativity and collaboration.

  • Literacy and Numeracy: Embedded across activities to improve communication and problem-solving skills.

PHYSICS IN DAILY LIFE

Core Principles and Applications

• Household Applications:

  • Appliances: A rice cooker converts electrical energy into heat through resistance heating. An electric fan promotes heat loss and evaporation by increasing air movement.

  • Cookware: Metal is preferred because it conducts heat well, whereas plastic is a poor conductor.

  • Lighting and Electricity: Flashlights convert electrical energy into light; wires heat up due to electrical resistance.

• Work Productivity and Tools:

  • Pulleys: Change the direction of applied force and can reduce effort by increasing the distance over which the force is applied.

  • Machines: Enhance efficiency through the application of force, motion, and energy transfer.

• Safety and Injury Prevention:

  • Newton’s Laws and Impulse: Safety devices like helmets, airbags, cushioned mats, and safety nets work by increasing the time of impact to reduce the force experienced by the body.

  • Friction: Helps people maintain balance and control movement; preventing slips on wet floors involves understanding friction thresholds.

• Leisure and Sports:

  • Motion and Gravity: Factors in sports like basketball (shooting force and trajectory) and roller coasters (transformation between potential and kinetic energy).

  • Sound and Light: Used in television, mobile phones, music, and gaming technologies.

Key Concepts Summary

• Motion: Change in position.

• Force: Needed to start, stop, or change the motion of objects.

• Heat: Transferred through conduction, convection, or radiation in household tasks.

• Electricity: Powers communication and household devices.

TRANSLATIONAL AND ROTATIONAL MOTION

Categorizing Motion

• Translational Motion: The entire body changes location from Point A to Point B. All points on the body move the same distance in the same direction.

• Rotational Motion: The body turns or spins around a fixed pivot or axis. Points on the body have varying linear displacements depending on their distance from the axis.

• Simultaneous Motion: Real-world objects often experience both types at once. Examples include a ball spinning while flying, a stone rolling downhill, or the wheels of a moving vehicle.

Comparison of Quantities

• Linear (Translational) Quantities:

  • Displacement ($\Delta x$): Measured in meters ($m$).

  • Velocity ($v$): Measured in meters per second ($m/s$).

  • Acceleration ($a$): Measured in meters per second squared ($m/s^2$).

• Angular (Rotational) Quantities:

  • Angular Displacement ($\theta$): Measured in radians ($rad$).

  • Angular Velocity ($\omega$): Measured in radians per second ($rad/s$).

  • Angular Acceleration ($\alpha$): Measured in radians per second squared ($rad/s^2$).

Practical Insights

• Radius and Velocity: A pitcher with longer arms (larger radius) can throw a ball faster than someone with shorter arms rotating at the same rate due to the relationship between linear and angular velocity.

• Safety and Injury: Understanding translational and rotational forces is critical in preventing brain injuries (e.g., standard foam in helmets prevents skull fractures from linear hits, while slip-liners manage rotational/twisting forces to prevent concussions).

SIMPLE AND COMPOUND MACHINES

Efficiency and Mechanical Advantage

• Efficiency: The ratio of useful output work to input work, expressed as a percentage ($\%$).

  • Formula: $\text{Efficiency} = \frac{\text{Output Work}}{\text{Input Work}} \times 100$

  • In real machines, efficiency is never $100\%$ because energy is lost to friction and heat.

• Mechanical Advantage (MA): The ratio of output force (load) to input force (effort). It indicates how much a machine multiplies force.

  • Formula: $MA = \frac{\text{Output Force}}{\text{Input Force}}$

Characteristics of Efficient Machines

• Low Friction: Reducing resistance through lubricants or smooth surfaces minimizes energy waste.

• Proper Alignment: Ensures force is applied effectively without loss.

• Optimized Design: Balancing distance and force to achieve the desired outcome with minimal effort.

Types of Machines

• Simple Machines: Single mechanisms (lever, pulley, wheel and axle, inclined plane, wedge, screw).

• Compound Machines: Two or more simple machines working together (e.g., bicycle, elevator, scissors).

THE PHYSICS OF FLUIDS

Pascal’s Principle

• Definition: Pressure applied to an enclosed fluid is transmitted equally in all directions throughout the fluid.

• Pressure Formula: $P = \frac{F}{A}$

  • $P$ = Pressure (measured in Pascals,$Pa$)

  • $F$ = Force (Newtons, $N$)

  • $A$ = Area (Square meters, $m^2$)

• Hydraulic Systems: Use Pascal's principle to multiply force. Because $P_1 = P_2$, a small force applied to a small area ($A_1$) results in a larger force on a larger area ($A_2$).

  • Relationship: $\frac{F_1}{A_1} = \frac{F_2}{A_2}$

  • Applications: Hydraulic car jacks, excavators, airplane brakes, and dentist chairs.

Archimedes’ Principle

• Definition: The buoyant force exerted on an object submerged in a fluid is equal to the weight of the fluid that the object displaces.

• Floating and Sinking:

  • An object floats if the fluid provides enough buoyant force to balance the object's weight.

  • Changing the shape or volume (e.g., the hull of a ship) allows even heavy metal to float by displacing more water.

• Impact of Physical Properties: Floating ability depends on the relationship between an object's mass, volume, and density.

LIGHT AND SOUND TECHONOLOGY

Properties of Waves

• Reflection: Bouncing of light or sound off a surface (e.g., mirrors, echolocation).

• Refraction: Bending of light as it passes between media (e.g., lenses, bent spoon in water).

• Amplitude: The height/intensity of the wave signal.

• Frequency: Number of cycles per second (related to pitch in sound and color in light).

• Wavelength: Distance between consecutive wave peaks.

Applications in Modern Technology

• Communication: Mobile phones, radios, and Wi-Fi utilize electromagnetic waves (specifically radio and microwaves).

• Navigation: GPS (Global Positioning System) uses microwave signals from satellites to determine locations on Earth.

• Medicine:

  • X-rays and Gamma Rays: Used for medical imaging and treatment.

  • Ultrasound: Uses reflected high-frequency sound waves to visualize internal organs or babies in the womb.

• Entertainment: Television, speakers, and holograms (3D images created via light interference).

• Innovations:

  • Lasers: Concentrated, non-divergent light used in surgery, barcode scanners, and fiber optics.

  • LEDs: Energy-efficient lighting with a long lifespan.

  • Soundproofing and Amplifiers: Absorption and concentration of sound waves (e.g., stethoscopes, recording studios).

CHEMISTRY IN OUR LIVES

Contibutions of Louis Pasteur

• Germ Theory of Disease: Disproved "Miasma theory" (bad air) and spontaneous generation; proved microorganisms cause disease, leading to improved hospital hygiene and sterilization.

• Pasteurization: A heating process that kills harmful microorganisms in milk and juice, extending shelf life and ensuring food safety.

• Vaccinology: Developed the first vaccines for rabies and anthrax using weakened strains of bacteria/viruses.

• Fermentation: Identified that microorganisms are responsible for fermentation in bread, yogurt, and wine.

• Molecular Asymmetry: Discovered the mirror-image nature of molecules.

Household and Personal Care Products

• Product Ingredients and Functions:

  • Sodium Hypochlorite ($NaClO$): Active ingredient in bleach for disinfecting and whitening.

  • Surfactants: Found in detergents and shampoos to remove dirt and grease.

  • Enzymes: Break down protein-based stains in laundry.

  • Sodium Fluoride: Found in toothpaste to strengthen enamel and prevent cavities.

  • Glycerin: Used in soap to retain skin moisture.

• Safety and Regulation:

  • FDA (Food and Drug Administration): Regulates personal care, cosmetics, and health products.

  • DTI (Department of Trade and Industry): Sets labeling and consumer safety standards.

  • DENR (Department of Environment and Natural Resources): Oversees environmental protection and hazardous waste disposal.

• Hazard Categories: Labeling includes symbols for Flammable ($\text{fire icon}$), Toxic ($\text{skull and crossbones}$), Corrosive, and Irritant.

• Proper Disposal: Consumers must follow product labels and local/DENR guidelines to prevent environmental contamination (e.g., not pouring chemicals down drains).

UTILIZATION OF ELECTRICITY

Hazards and Safety Practices

• Overloading: Connecting too many devices to one outlet causes overheating and fire risks.

• Damaged Insulation: Exposed wires increase electrocution risks; they must be replaced, not just taped over.

• Damp Conditions: Water conducts electricity; wet hands or submerged outlets pose a lethal shock risk. Use Ground Fault Circuit Interrupters (GFCI) in these areas.

• Faulty Wiring: Loose connections or poor installations require a licensed electrician.

• Grounding: A green or bare copper wire that provides a low-resistance path for fault current to dissipate safely into the earth.

Emergency Response

• Electrocution: Never touch the victim directly; turn off the power source first or use a non-conductive object (wood/rubber) to separate them from the source.

• Electrical Fires: Use a $\text{CO}_2$ extinguisher (Class C). Never use water as it conducts electricity.

Energy Conservation

• RA 11285 (Energy Efficiency and Conservation Act): Institutionalizes energy efficiency as a national way of life and provides incentives for conservation projects.

• Energy Loss vs. Wastage:

  • Energy Loss: Mechanical/physical dissipation due to poor equipment (e.g., cracked refrigerator seals).

  • Energy Wastage: Behavioral/unnecessary use (e.g., leaving lights on in empty rooms, standby power from plugged-in chargers).

• Sustainability: Implementing renewable sources and efficient habits contributes to Global Goals (SDG 7, 12, and 13).",  "title": "Senior High School General Science Core Subject Study Guide" } ```