Question | Answer |
Law of Conservation of Energy | Energy can NOT be created or destroyed... but it CAN change forms. |
Potential Energy | Stored energy |
Kinetic Energy | Energy of movement |
Force | A push or a pull on an object |
Balanced Force | Does NOT change the speed or direction of the object |
Unbalanced Force | Changes the speed and/or direction of the object in the direction of the stronger force |
Law of Gravity | The force of attraction between objects. Its strength depends on the mass of the objects and their distance from each other. |
Speed (Velocity) | Distance divided by time |
Mechanical Energy | The combined energy of motion (kinetic) and position (potential) |
Chemical Energy | Energy stored in chemical bonds |
Thermal Energy | Heat |
Sound Energy | Vibrations |
Radiation | Energy that can travel through empty space EX: heat from the sun |
Reflection | When light bounces off a surface Ex: a mirror |
Refraction | When light bends as it goes through a material Ex: objects look larger/distorted in water |
Absorption | When light stops at the object and is not reflected or refracted |
Waves | How energy moves |
Chemical Property | A property that involves changing the substance into something else Ex: the ability to rust or burn |
Physical Property | A property that can be observed without changing the substance |
Density | Mass divided by Volume |
Volume | The amount of space an object fills |
Mass | The amount of matter in an object |
Weight | The amount of gravity pulling on an object. This can change if you go to another planet. |
Chemical Change | Changes what a substance IS. Ex: Burning wood turns to ash |
Physical Change | Changes the appearance of an object, it it is still the same substance. Ex: tearing a piece of paper |
Atom | The smallest unit of an element |
Protons | Positive charge, found in the nucleus |
Neutron | Neutral charge, found in the nucleus |
Electron | Negative charge, found in the electron cloud |
Element | One type of atom, represented by each square of the periodic table |
Molecule | More than one atom joined together |
Solid | Atoms are tightly packed together. Have constant shape and volume. |
Liquid | Atoms are more loosely packed. The volume is constant, but the shape can change. |
Acid | pH of 0-6. Sour taste, react with metals. Ex: citrus juice, vinegar |
Base | pH of 8-14. Bitter taste, feel slippery. Ex: Soap, ammonia, baking soda |
Neutral | pH of 7. Ex: water |
Homogeneous Mixture | substances are combined and can not be easily separated |
Heterogeneous Mixture | substances can be easily separated |
Gas | Atoms are spread far apart and move around freely. Can change volume and shape. |