FOSS Science

Water Planet

Study Guide

Investigation 1:

What is the Sun? The Sun is an average star, composed mostly of hydrogen (72) and helium (26%), around which the other solar system bodies revolve. It is the star closest to the Earth.

What is the solar system? The solar system is the Sun and all the bodies that orbit it, including planets and their moons, asteroids, and comets.

What is gravity? Gravity is the force of attraction between two objects; larger bodies, like the Sun, have a greater force of gravity.

Why do planets travel around the Sun in circular paths? Gravity pulls on planets with a force that changes their direction of travel from a straight line into a circle.

Compare and contrast asteroids and comets. Both orbit the sun and are smaller than planets. Comets are rock mixed with ice while asteroids are just rock. Comets are farther from the Sun.

Investigation 2:

What is a variable? A variableis anything that you can change in an experiment that might affect the outcome.

What variable might affect the number of cycles the pendulum makes in 15 seconds? Mass, length, and starting position

Where have you seen a pendulum? In an old clock, at a museum, as a playground swing, in a metronome

What variables made no difference in the number of swings? Mass and release position

Which variable did make a difference in the number of swings? Length

What is the relationship between the length of the pendulum and the number of swings it makes in a unit of time? As the length of the pendulum increases, the number of swings decreases

What is a two-coordinate graph? A display of experimental data that shows a relationship between an independent variable and a dependent variable

What is a prediction? A reasoned estimation of a future event based on context, data, or experience

Who was Galileo Galilei? Galileo was a man who changed the science of astronomy. He was the 1st to use a telescope to look at the solar system. He described features of Mars, Jupiter, and Saturn. He made the 1st maps of the Moon’s surface and discovered satellites orbiting Jupiter.

Investigation 3:

What happens to a wet paper towel in an open cup? It becomes dry when the liquid evaporates

What happens to the water in a paper towel when it evaporates? It changes into water vapor and moves into the air

Where does the most evaporation happen? At the warmest place

Where does the least evaporation happen? At the coolest place

How does the surface area of a volume of water affect evaporation? The larger the surface area of a volume of water, the faster the water evaporates

Where does the water that forms on the outside of a cup of ice water come from? When water vapor in the air touches a cool surface, it condenses into liquid

What causes frost to form? When water condenses on surfaces that are below the freezing point for water (0ºC), the water freezes to form frost

How does temperature affect the amount of water vapor in the air? Warm air holds more water vapor than cool air

Is warm air less dense or more dense than cold air? It is less dense

Investigation 4:

Is hot water denser or less dense than room-temperature water? Hot wateris less dense than room-temperature water. How do you know? It floats in room-temperature water.

Which is denser, hot water or cold water? Cold water is denser than hot water. How do you know? It sinks in room temperature water while hot water floats on room temperature water.

What causes a convection current? A convection current occurs when the bottom of a mass of fluid is heated. The warm water rises, cools, and then descends, creating a circular flow.

What happens when air is pushed in to a smaller space? Air molecules move closer together, resulting in compressed air.

What causes atmospheric pressure? The weight of air

What is a heat sink? It is any material that can absorb heat. Water is a good heat sink because it holds a lot of heat. Soil is not a good heat sink because it heats up and cools down quickly.

What happens when light is absorbed by matter? The matter gains energy and its temperature goes up.

What variables affect how hot a material will get when the Sun shines on it? How hot a material gets depends on the length of exposure, the intensity of the solar energy, the color of the material, and the properties of the material.

Investigation 5:

Where is most of earth’s water found? In the oceans

What percent of the Earth’s water is fresh water? 3%

What percent of Earth’s surface is covered by water? 71%

Where is earth’s fresh water found? In the atmosphere, rivers, lakes, glaciers, groundwater, animals, and plants

How is water recycled on earth? Water is redistributed and recycled by evaporation, condensation, precipitation, and flow, a sequential process called the water cycle. There is only a certain amount of water on Earth, no more is being made.

What is the sun’s role in weather? Solar energy is responsible for all weather and all changes of weather. Solar energy heats earth’s surface, evaporates water, and drives wind

What is the ocean’s role in weather? Oceans are the main source of water vapor for precipitation. Oceans also moderate temperatures along coastlines.

How are weather data obtained? Meteorologists use weather instruments on the ground, radiosondes on balloons, and satellite images to obtain surface and atmospheric measurements of weather variables.

What kinds of data are displayed on weather maps? Weather maps display atmospheric pressure, weather fronts, and precipitation

What is most fresh water used for in California? Agriculture

What is a cause and effect of floods in California? Heavy rain or snow melts can cause flooding; a result could be mudslides

What is the cause and effect of droughts in California? One result of too little rain is crop failure

What can result from Increased or decreased pressure on an air mass? Severe weather, wind, fog, and precipitation

How does the Pacific Ocean affect the weather along the California coast? It creates mild temperatures along the coast, is a source of water for rain and snow, and causes coastal breezes due to uneven heating