Science Ch.12.3-12.4 Flashcards
What is Law of Conservation of Mass?
Law stating that the total momentum of a system does not change if no net force acts the system.
What is momentum?
The product of an object’s mass and it’s velocity.
What is centripetal force?
A force that continuously changes the direction of an object to make it move in a circle.
What is weak nuclear force?
A powerful attractive force that act over a short range
What is gravitational force?
An attractive force that acts between any two objects.
What is electromagnetic force?
A force associated with charged particles, which has two aspects, electric force and magnetic force.
What is strong nuclear force?
The powerful attractive force that binds protons and neutrons together in the nucleus.
What is momentum measured in?
Kg•m/s
Kilograms•meters per second
What two things are multiplied to calculate to momentum?
Mass and velocity
According to Newton’s third law of motion, what happens whenever one object exerts a force on a second object?
Whenever one object releases force on another that object releases the same amount of force back.
The equal and opposite forces described by Newton’s third law are called ______ and _______ forces.
Action and reaction
What are the two factors that affects the momentum of a moving object?
Mass and velocity
If two identical objects are moving at different velocities, the object that is moving faster will have _______ momentum.
Greater
If an object is not moving then what is it’s momentum?
0 kg•m/s
What is formula momentum?
Momentum(kg•m/s)=mass(kg)•velocity
(m/s)
Is the true or false? Objects within a closed system can exert forces on one another, but other objects and forces cannot leave or enter the system.
True
What is difference between strong and week nuclear forces?
Strong-acts on the particles neutrons and protons, acts at very short distance,very strong(100 times stronger than an electric force)
Weak-acts on all particles, acts on a short distance, and weaker than the strong force
What are the four universal forces?
Electromagnetic, strong nuclear, weak nuclear, gravitational
Name the only two forces that can both attract and repel.
Electric and magnetic
What evidence suggests that nuclear forces have a powerful force of attraction?
They hold nucleus together
State Newton’s law of universal gravitation.
Every object in the universe attracts every other object in the universe.
The gravitational force of attraction between two objects depends on ______ and _______.
Mass and distance
The sun’s mass is much greater than the mass of Earth, so the sun’s gravitational force is much _______ than that of Earth.
Stronger
Is this true or false? The gravitational pull of the moon is the primary cause of Earth’s ocean tides.
True
List four uses of artificial satellites.
- monitor Earth’s weather
- create detailed radar maps of Earth’s surface
- use telescopes to gaze into space
- receive and transmit cell phone and satellite television signals
Why does the moon continue is circular path around Earth?
Because of centripetal force
