Types of Forces
This force pulls objects toward each other, most noticeably toward Earth.
What is gravity?
If two equal forces act on an object in opposite directions, the forces are said to be this.
What is balanced?
This type of change forms a new substance with different properties.
What is a chemical change?
The formula for density is this.
What is mass divided by volume (D = m/v)?
The three main states of matter are these.
What are solid, liquid, and gas?
This force opposes motion between two surfaces that are in contact.
What is friction?
If an object is accelerating, the forces acting on it must be this.
What is unbalanced?
This type of change alters the appearance of a substance but not what it’s made of.
What is a physical change?
An object with a density higher than water will do this in water.
What is sink?
In this state, particles are tightly packed and vibrate in place.
What is a solid?
This type of force occurs when an object is pushed or pulled by another object or person.
What is applied force?
Two people push a box: one with 20 N to the right, one with 15 N to the left. What is the net force?
What is 5 N to the right?
Halloween originated from this ancient Celtic festival that celebrated the end of the harvest season.
An object has a mass of 60 g and a volume of 30 mL. What is its density?
What is 2 g/mL?
This state of matter has a definite volume but no definite shape.
What is a liquid?
This is the upward force that keeps an object from falling through a surface.
What is the normal force (support force)?
An object has 10 N pushing left and 25 N pushing right. What happens to the object?
It accelerates to the right.
Burning wood, rusting iron, and baking a cake are examples of what type of change?
What are chemical changes?
Two objects have the same mass, but one has a larger volume. Which one is less dense?
The one with the larger volume.
This state of matter has no definite shape or volume.
What is a gas?
This force acts between objects that touch each other and resists motion.
What is contact force (or frictional force)?
A car is moving at a constant speed on a straight road. What can you say about the net force?
It is zero (forces are balanced).
The process of breaking and forming bonds between atoms to create new substances is called what?
What is a chemical reaction?
Why does oil float on water?
Because oil is less dense than water.
This state of matter is made of charged particles and found in stars and
What is plasma?