Chapter 12.3 & 12.4
According to the law of conservation of momentum, what happens to the total momentum of a system if no net force acts on the system?
Total momentum of a system does not change.
Is the following sentence true or false? An object with a small mass can have a large momentum if the object is traveling at a high speed.
True
Is the following sentence true or false? In a closed system with two objects, the loss of momentum of one object equals to the gain in momentum of the other object.
True
Is the following sentence 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
Is the following statement true or false? Action-reaction forces do not cancel each other because the action force is always greater than the reaction force.
True
True or false? The centripetal force is a center directed force that changes the direction of an object to make it in a circle.
True
True or false? The gravitational force between two objects increases as distance decreases.
True
True or false? The universal force that is the most effective over the longest distance is gravitational force.
True
The equal and opposite forces described by Newton's third law are called ___ and ___ forces.
Action, reaction
What force is responsible for the repulsion between two positively-charged particles?
Electric
What are universal forces?
Electromagnetic, nuclear, gravitational
What is Newton's law of Gravity?
Every object in the universe attracts every other object.
True or false? The gravitational force between two objects increases as mass decreases.
False
______ - force of friction through a fluid.
Fluid friction
The combination of an initial _____ velocity and the downward ____ force of gravity causes the ball to follow a ____ path.
Forward, vertical, curved
What is the primary cause of Earth's ocean tides?
Gravity
What is the weakest universal force?
Gravity
What does conservation of momentum mean?
If no net force acts on a system, then the total momentum of the system does not change.
What's a strong nuclear force?
It acts only on the protons and neutrons in the nucleus. It holds the nucleus together.
What is a nuclear force?
It's a force that acts within an atom that holds it together.
What is a weak nuclear force?
Keeps the nucleus together by binding the smaller particles.
If two identical objects are moving at different velocities, the object that is moving faster will have ___ momentum.
Larger
Momentum is calculated by multiplying ___ and ___
Mass, velocity
What is the law of conservation of momentum?
Momentum neither increases nor decreases.
Gravity is a force that acts between any two ___. Gravity is an ____ force (masses will ___ each other closer together).
Objects, attractive, pull
Friction - a force that ___ the motion of objects that touch as they move past each other.
Opposes
___ - the frictional force that acts on rolling objects.
Rolling friction
___ - a force that opposes the direction of motion of an object as it ___ over a surface.
Sliding friction, slides
___ - the friction force that acts in objects that are _____
Static friction, not moving
According to Newton's third law of motion, what happens whenever one object exerts a force on a second object?
The second object exerts an equal and opposite force on the first object.