Physics: Motion, Speed, Measurement, Electricity, Magnetism

Motion

• Motion describes a change in an object's position relative to time.
• Objects in motion change their position relative to a reference point.
• Linear, circular, and periodic are types of motion.

Speed

• Speed is an object's rate of movement.
• Speed is calculated by dividing distance traveled by time: Speed = Distance / Time.
• Meters per second (m/s) is the standard unit of measurement.

Measurement

• Measurement determines the size, quantity, or extent of something.
• Accurate measurement is crucial for scientific experiments.
• Common measurements include length, mass, time, and temperature.

Electricity

• Electricity is a form of energy from charged particles.
• Electric circuits allow electric current to flow.
• Source, wires, and a load compose a basic circuit.
• Conductors facilitate electrical flow, whereas insulators inhibit it.

Magnetism

• Magnetism is the force magnets use to attract or repel.
• Magnets have north and south poles.
• Like poles repel, and opposite poles attract.
• A magnetic field surrounds a magnet, where its force is exerted.

Light

• Light is electromagnetic radiation that enables vision.
• Light travels in a straight line.
• Reflection occurs when light bounces back from a surface.
• Refraction is the bending of light as it moves from one medium to another.

Shadows

• Shadows form when an object obstructs light.
• Shadow shape and size depend on the object's size and shape, and position of the light source.
• Opaque objects cast dark shadows, while translucent objects cast faint shadows.

Simple Circuits

• A simple circuit includes a power source, wires, and a load, like a bulb.
• The circuit must be closed for electricity to flow and light the bulb.
• Switches control electrical flow by opening or closing a circuit.

Electric Cells

• An electric cell (battery) provides power to a circuit.
• Cells convert chemical energy into electrical energy.
• Cells have positive and negative terminals.

Magnets

• Magnets attract iron, nickel, and cobalt.
• Magnets have north and south poles.
• Compasses use a magnetic needle to indicate direction based on Earth's magnetic field.

Water Cycle

• The water cycle is the continuous movement of water on, above, and below Earth's surface.
• Key processes include evaporation, condensation, precipitation, and collection.
• Evaporation is when water changes from liquid to gas.
• Condensation occurs when water vapor changes into liquid.
• Precipitation includes rain, snow, sleet, and hail.

Air

• Air primarily consists of nitrogen and oxygen.
• Air also contains carbon dioxide, argon, and water vapor.
• Air is essential for living organisms.

Properties of Air

• Air occupies space and has weight.
• Air exerts pressure.
• Air expands when heated and contracts when cooled.

Soil

• Soil is the uppermost layer of Earth's crust, containing minerals, organic matter, water, and air.
• Soil supports plant life.
• Soil forms through weathering of rocks and decomposition of organic matter.

Types of Soil

• Sandy, clayey, and loamy soil types are based on particle size.
• Sandy soil has large particles, drains quickly, and does not retain water.
• Clayey soil has fine particles, retains water well, and can become waterlogged.
• Loamy soil is a mixture of sand, silt, and clay, balancing drainage and water retention.

Living Organisms and Their Surroundings

• Living organisms interact with and depend on their environment for survival.
• Habitats are natural environments where organisms live.
• Adaptation helps organisms adjust to their environment.

Characteristics of Living Organisms

• Living organisms need food, water, and air.
• They grow, reproduce, move, and respond to stimuli.
• They excrete waste products.

Plants

• Plants are living organisms that produce their own food through photosynthesis.
• Chlorophyll is the green pigment in plants that captures sunlight for photosynthesis.
• Plants have roots, stems, leaves, flowers, and fruits.

Parts of a Plant

• Roots anchor the plant and absorb water and nutrients.
• Stems support the plant and transport water and nutrients.
• Leaves facilitate photosynthesis.
• Flowers enable reproduction.
• Fruits contain seeds.

Food

• Food provides energy and nutrients for living organisms.
• Nutrients include carbohydrates, proteins, fats, vitamins, and minerals.
• A balanced diet is essential for good health.

Sources of Food

• Plants and animals are the main food sources.
• Plant-based foods include fruits, vegetables, grains, and legumes.
• Animal-based foods include meat, dairy, and eggs.

Fabrics

• Fabrics are materials made from fibers.
• Fibers can be natural or synthetic.
• Natural fibers include cotton, wool, silk, and linen.
• Synthetic fibers include nylon, polyester, and rayon.

Types of Fabrics

• Cotton is soft, absorbent, and breathable.
• Wool is warm and durable.
• Silk is smooth and lustrous.
• Linen is strong and absorbent.

Changes Around Us

• Changes can be physical or chemical.
• Physical changes alter a substance's form or appearance without changing its chemical composition.
• Chemical changes create new substances.

Examples of Changes

• Melting, freezing, boiling, and evaporation are physical changes.
• Burning, rusting, and cooking are chemical changes.

Motion and Measurement of Distances

• Accurate measurement is essential in everyday life and science.
• Standard length units include meters and centimeters.
• Rulers, measuring tapes, and odometers measure length.