Test Reveiw 1 - Grade 7 Flashcards
Physical science
the study of matter, energy, and the changes they undergo.
Energy
Energy is the ability to do work.
Matter
Anything that has mass or takes up space.
Chemistry
The study of the properties of matter and how matter changes.
Science
A process of gathering knowledge about the natural world.
Physics
The study of matter and energy and how they interact.
How do we measure matter?
System International (SI) The metric system
Mass
The amount of matter in the object
Measured in grams (g), kilograms (kg), triple beam balance
Measured by: electronic balance, triple beam balance
Length
THe distance from one point to another on a straight line
Measured in: meters (m), kilometers (km), centimeters (cm), millimeters (mm)
Measured in: metric ruler, meter stick, metric tape
Weight
A measure of the force of gravity on an object
Measured in: newtons
Measured by: Spring Scale
Volume
That amount of space an object takes up
Measured in: liter (L), millimeter (ml) (liquid)
Measured by: metric ruler, beaker, radiated cylinder
Density
I love (mv) density
The amount of matter in a certain space
Measured in grams
KHDBDCM
Kilo Hecto Deka Base Unit Deci Centi Milli
Model
A representation of an object or system Types: Physical models Mathematical Models Conceptual Models
Physical Models
Ex: Globe, Cell Model
Mathematical Models
Ex: e=mc2, weather forecast
Conceptual Models
Ex: time, the Big Bang
Theory
An explanation for many hypotheses and and observations
Ex: theory of relativity
Law
A summary of many experimental results and observations. A law tells you how things work. Laws are not the same as theories. Laws only tell you what happens, not why it happens.
Ex: law of gravity
Physical Property
Information about matter that can be observed or measured without changing the matters identity.
Ex: color, texture, volume, weight, height, Oder, magnetism, conductor of electricity, strength, flexibility, density
State of matter
Solid, liquid, gas
Thermal Conductivity
The rate at which a substance transfers heat. Plastic foam is a poor conductor.
Solubility
The ability of a substance to dissolve in another substance. Flavored drink mix dissolves in water. Property: soluble. Solute dissolves into the solvent.
Ductility (Ductile)
The ability to be pulled into a wire. Copper is often used to make wiring, because it is ductile.
