Term |
Definition |
How fast the position of an object changes is its |
speed |
An object's speed in a certain direction if its |
velocity |
A change in a velocity in a certain amount of time is called |
acceleration |
How much an object weighs depends on its mass and the force of |
gravity |
An object's tendency to resist a change in motion is its |
inertia |
An astronaut on the moon has the same mass as she did on Earth, but has less |
weight |
For every action, there is an equal but opposite |
reaction |
Pushes or pulls which completely cancel one another out are called |
balanced forces |
A push or pull that acts on an object is called a(an) |
force |
Pushes or pulls which are not cancelled by other pushes or pulls are called |
unbalanced forces |
Gravity is a |
force |
When object A exerts a force on object B, object B |
exerts a reaction force on object A |
A mass accelerates because |
a force is acting on it |
A baseball and a sheet of paper are dropped at the same time from the same height. If there is no air rresistance |
the baseball and the paper will land at the same time |