https://teddyrookbook.com/physics/science-explorers/Recent content in Science Explorers (ages 9–10) on Teddy Rook Bookhttps://teddyrookbook.com/img/share.jpghttps://teddyrookbook.com/img/share.jpgHugoenhttps://teddyrookbook.com/physics/science-explorers/observe-question/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/observe-question/Scientists look closely, use their senses and tools, and ask questions they can test. An observation is what you notice; a guess about why is a hypothesis. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/fair-test/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/fair-test/In a fair test you change only one thing, keep everything else the same, and measure what happens. Then you can tell what made the difference. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/measure/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/measure/Length in centimeters and meters, mass in grams and kilograms, liquid volume in milliliters and liters, and temperature in degrees. Read the scale at eye level. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/what-is-matter/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/what-is-matter/Matter is anything that has mass and takes up space. Air is matter too: a balloon gets bigger when you fill it, and a full ball weighs a little more than a flat one. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/three-states/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/three-states/A solid keeps its own shape. A liquid takes the shape of its container but keeps its amount. A gas spreads out to fill any container. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/changing-state/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/changing-state/Heating can melt a solid into a liquid and turn a liquid into a gas. Cooling does the reverse. Water freezes at 0 °C (32 °F) and boils at 100 °C (212 °F) at sea level. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/mixtures-solutions/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/mixtures-solutions/A mixture is two or more things mixed together that keep their own properties. In a solution, one thing dissolves evenly into another, like salt in water. The total mass stays the same. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/new-substances/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/new-substances/A physical change (cutting, melting, dissolving) keeps the same substance. A chemical change makes a new substance: signs are a gas, a new color, light, heat or a smell. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/pushes-pulls/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/pushes-pulls/A force is a push or a pull. Forces can start something moving, stop it, speed it up, slow it down or change its direction. Balanced forces cancel; unbalanced forces change motion. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/friction-gravity/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/friction-gravity/Friction is a force that rubs against motion; rough surfaces make more of it. Gravity pulls things toward the center of the Earth, so dropped things fall down. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/levers/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/levers/A lever is a stiff bar that turns on a point called the fulcrum. Pushing far from the fulcrum lets a small push lift a big load. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/wheels-pulleys/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/wheels-pulleys/A wheel and axle turn together: a small turn of the axle makes a big turn of the wheel, or the other way. A pulley is a wheel with a rope; a movable pulley halves the pull you need. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/ramps-wedges-screws/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/ramps-wedges-screws/A ramp (inclined plane) lets you raise a load with a smaller push over a longer path. A wedge is two ramps back to back that split things apart. A screw is a ramp wrapped around a post. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/energy-forms/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/energy-forms/Energy is what makes things move, light up, heat up or make sound. Its forms include motion, stored (in food, batteries, a stretched rubber band or something high up), heat, light, sound and electrical energy. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/energy-changes/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/energy-changes/Energy is never used up; it changes from one form to another. A flashlight turns stored energy in the battery into electrical energy, then light and some heat. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/heat-moves/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/heat-moves/Heat moves from warmer things to cooler things. It moves by touching (conduction), by moving air or water (convection) and by rays like sunshine (radiation). Insulators slow it down. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/magnets/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/magnets/A magnet has a north pole and a south pole. Opposite poles attract and like poles repel. Magnets pull on iron and steel, but not on wood, plastic, paper, glass or most coins. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/circuits/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/circuits/Electricity flows only around a complete loop called a closed circuit: from the battery, through the wires and the bulb, and back. A switch opens the loop to turn the bulb off. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/conductors-insulators/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/conductors-insulators/Conductors, like metals, let electricity flow through them. Insulators, like plastic, rubber, wood and glass, do not. Wires are metal inside and plastic outside. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/electromagnets/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/electromagnets/Electricity flowing through a coil of wire makes a magnet that can be turned on and off. Electromagnets lift scrap metal and turn the motors in fans and toys. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/light-shadows/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/light-shadows/Light travels in straight lines. When something blocks it, a shadow forms on the other side. The closer the object is to the light, the bigger its shadow. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/mirrors-bending/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/mirrors-bending/Light bounces off a mirror at the same angle it hits it. Light bends when it passes from air into water or glass, so a straw in a glass looks broken. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/colors/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/colors/White light is a mix of all the colors of the rainbow: red, orange, yellow, green, blue, indigo and violet. A prism or raindrops spread them out. A red apple looks red because it reflects red light. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/sound/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/sound/Sound is made when something vibrates. Fast vibrations make a high pitch; slow ones a low pitch. Bigger vibrations are louder. Sound travels through air, water and solids, but not through empty space. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/water-cycle/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/water-cycle/The Sun warms water so it evaporates into vapor. The vapor rises, cools and condenses into clouds. Water falls as rain or snow (precipitation) and collects in oceans, lakes, rivers and the ground. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/weather/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/weather/Weather is the air outside today: temperature, wind, clouds and rain. A thermometer measures temperature, a rain gauge rain, a wind vane wind direction and an anemometer wind speed. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/rocks-minerals/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/rocks-minerals/Rocks are made of minerals. Igneous rock forms when melted rock cools, sedimentary rock from layers of sand and mud pressed together, and metamorphic rock when heat and pressure change a rock. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/weathering-erosion/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/weathering-erosion/Weathering breaks rock into smaller pieces; water, ice, wind and plant roots all do it. Erosion carries the pieces away, and they are dropped somewhere else, building new land. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/plants-make-food/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/plants-make-food/Plants make their own food (a sugar) in their leaves from sunlight, water and carbon dioxide from the air. They give off oxygen. Roots take in water; they do not "eat" soil. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/food-webs/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/food-webs/Energy starts with the Sun. Producers (plants) make food; consumers eat plants or other animals; decomposers break down dead things. A food web is many food chains joined together. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/adaptations/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/adaptations/An adaptation is a body part or behavior that helps a living thing survive where it lives: a camel's hump of fat, a duck's webbed feet, a cactus's spines and waxy skin, birds flying south. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/human-body/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/human-body/Body systems work together. Bones hold you up and muscles move them. The heart pumps blood; the lungs bring in oxygen; the stomach and intestines break down food; the brain and nerves send messages. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/day-night/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/day-night/The Earth spins once about every 24 hours. The side facing the Sun has day; the other side has night. The Sun seems to rise in the east and set in the west because the Earth turns. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/moon-phases/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/moon-phases/The Moon makes no light of its own; it reflects sunlight. As it goes around the Earth, about once a month, we see more or less of its sunlit half: new, crescent, quarter, gibbous and full. Science Explorers (ages 9–10) · Physics Ladderhttps://teddyrookbook.com/physics/science-explorers/solar-system/Mon, 01 Jan 0001 00:00:00 +0000https://teddyrookbook.com/physics/science-explorers/solar-system/The Sun is a star, the closest one to us. Eight planets go around it: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Gravity keeps them in their orbits. Science Explorers (ages 9–10) · Physics Ladder