Forces In Interactions
A push or pull on an object is called ______
Force
The net force on an object is found by ___________.
adding or subtracting the forces
What two factors determine the strength of the gravitational force between two objects?
mass; distance
What are the two kinds of electric charge?
Positive and negative
Every magnet has a _____ and _____ pole.
north; south
What unit is used to measure the strength of forces?
Newtons
Balanced forces have a net force of ____ N.
0
A feather fall does not fall at the same rate as an apple due to ____ ________ .
air resistance
Positive and negative charges are represented in field diagrams by _____ and ______ signs.
plus; minus
An _________ is a magnet with a current-carrying wire.
electromagnet
Newton's ____ law of motion states that for every action there is an opposite and equal reaction.
third
If four dogs pull a sled with a force of 25N each, what would be their net force?
100N
Forces pulling together are called _________ forces.
attractive
A positively charged balloon is repulsed by another balloon nearby, we know that the other balloon must be _________ charged.
positively
The magnetic forces between poles are ______ when the poles are opposite, and ______ when the poles are similar
attractive; repulsive
What was an “old” idea that Newton was taught while he was in school?
Earth was the center of the solar system.
Friction is a force that works in the _____________ direction of an object’s motion.
opposite
A map of a force field that can be used to predict which way gravitational forces will pull an object is called a ________ ______.
Electric forces that are closer together are _______ whereas electric forces that are farther apart are ________.
stronger; weaker
Earth’s geographic north pole is also Earth’s magnetic ______ pole.
south
Astronauts train for EVAs by practicing the tasks they will be doing in space __________.
underwater
What are the three components of the equation for Newton's second law of motion?
Acceleration, mass, and force
An astronaut's mass on the moon and on earth will always be the ________ while their weight will always be ______.
A flow of particles with electric charge is called an electric ________.
current
An object that uses motion to create energy is called an electric ________ whereas an object that uses electricity to create motion is called an electric ______.
generator; motor