Energy
A soccer player kicks a ball across the field. What causes the ball to start moving?
A force from the player’s foot causes the ball to move.
A student touches a metal spoon and a wooden spoon that have both been sitting in hot soup. Which spoon will feel hotter, and why?
The metal spoon will feel hotter because metal transfers thermal energy faster than wood.
A student mixes sand and water in a cup. Did a new substance form, or is this a mixture?
This is a mixture because the sand and water are combined, but no new substance is formed.
A student looks at the sky and sees only half of the Moon lit up. What causes the Moon to appear to change shape throughout the month?
The Moon appears to change shape because the Moon orbits Earth, and we see different amounts of sunlight reflected off the Moon.
A person starts running. Their breathing gets faster, and their heart beats faster.
Which two body systems are working together to help maintain balance in the body?
The respiratory system and circulatory system are working together to bring oxygen to cells and remove carbon dioxide. This helps maintain Homeostasis homeostasis.
A student pushes two carts with the same amount of force. One cart is empty, and one cart is full of books. Which cart will speed up more?
The empty cart will speed up more because it has less mass.
A student creates two waves using the same rope.
Both waves move at the same speed. Which wave has more energy, and what evidence supports your answer?
Wave B has more energy because it has a greater amplitude. Waves with greater amplitude carry more energy.
A student observes two clear liquids being mixed. After mixing, bubbles form and a new odor is produced. What most likely occurred, and what evidence supports your answer?
A chemical reaction most likely occurred. Evidence includes gas production (bubbles) and a new odor.
Earth stays in orbit around the Sun, and the Moon stays in orbit around Earth. What force keeps these objects moving in orbit?
Gravity Gravity keeps Earth orbiting the Sun and the Moon orbiting Earth.
A student touches a hot stove and quickly pulls their hand away. What caused the student to react so quickly?
Sensory receptors detected the heat (stimulus) and sent signals to the nervous system, causing an immediate response.
A book is moved from the floor to the top shelf.
How does the book’s potential energy change?
The book’s potential energy increases because it is higher above the ground.
Two waves are shown:
Wave B has the greater frequency because it has more waves passing in one second.
A model of a substance shows:
⚪⚪ = two atoms of the same element
⚪⚫⚫ = three atoms made of two different elements
Which model represents a molecule, and how do you know?
⚪⚫⚫ represents a molecule because it contains two or more atoms bonded together, including different types of atoms.
Scientists found the same fossil on the east coast of South America and the west coast of Africa.
What does this evidence suggest about these continents long ago?
This suggests the continents were once connected and later moved apart because of plate motion.
A plant is placed in sunlight with water and carbon dioxide.
What process allows the plant to make its own food?
The plant uses Photosynthesis photosynthesis to make food (glucose) using sunlight, water, and carbon dioxide.
A student rolls two balls down the same ramp:
Both travel at the same speed. Which ball has more kinetic energy and why?
Ball B has more kinetic energy because kinetic energy increases as mass increases, even when speed stays the same.
A student shines a flashlight at three materials:
A student places vinegar and baking soda in a sealed bag and measures the mass before and after the reaction. The mass stays the same. What scientific principle does this demonstrate?
This demonstrates the Law of Conservation of Mass Law of Conservation of Mass, matter is not created or destroyed during a chemical reaction.
A student creates a model showing this pathway:
Ocean → water vapor → clouds → rain → river → ocean
Identify two forces or energy sources that drive this cycle and explain their role.
In a forest, a long drought causes less water to be available. Over time, fewer plants begin to grow.
How will this most likely affect the deer population in the forest?
The deer population will most likely decrease because there is less plant food available. Fewer resources can lead to smaller populations.
A student uses two different magnets to pick up paper clips. Magnet A picks up 3 paper clips, while Magnet B picks up 8 paper clips. What question could the student ask to investigate why Magnet B is stronger?
How does the size or strength of a magnet affect how many paper clips it can pick up?
A student is designing a lunch box that keeps food warm for the longest amount of time. They can choose:
Thick foam insulation would be the best choice because it minimizes thermal energy transfer better than cardboard or metal. Foam traps air, which slows the movement of thermal energy and helps keep the food warm longer.
A student builds a model of a chemical reaction. Before the reaction, there are:
After the reaction, the atoms are rearranged into new molecules.
How many red and blue atoms must be present after the reaction, and why?
There must still be 2 red atoms and 4 blue atoms because atoms can rearrange, but the total number of each type of atom stays the same during a chemical reaction.
A student is learning about three types of tectonic plate boundaries:
A lizard lays eggs without needing another parent. The baby lizards look almost exactly like the parent.
What type of reproduction occurred, and how will the offspring most likely compare genetically to the parent?
This is asexual reproduction. The offspring will have genetic information that is nearly identical to the parent.