Net force and balanced and unbalanced forces
If there are two equal forces on an object, what happens?
They cancel out
What force opposes the motion of objects sliding against each other?
Friction
Define weight
The force of gravity on an object’s mass.
If you get pushed against the wall and the wall pushes you back, what law is that?
3rd law
What are the units for the acceleration of gravity on Earth?
9.81 m/s^2
If a box has 5N pushing down, 5N pushing up, and 10N pushing left, which direction will it move?
Left
What force pulls objects toward the center of the Earth?
Gravity
David, who is an astronaut, has a mass of 40kg. What is his mass when he travels to the moon?
40 kg
Why does more mass result in more force and which law supports this idea?
2nd law
What is terminal velocity?
When the object falling at a constant speed reaches a point where its resistance equals the gravitational pull.
What does a balanced force do to an object?
Keeps it at rest or in constant motion
What force opposes the motion of an object moving through air?
Air resistance
How does the moon’s smaller mass affect its gravitational pull? What is the gravitational pull?
It makes it less- 1.6 m/s/s
What is another name for Newton's First Law of Motion?
Law of inertia
What is the difference between terminal velocity and free fall?
Terminal velocity is constant and between air resistance and gravitational pull acting upon the object, but a free fall only has gravitational pull acting upon the object.
What does an unbalanced force do to an object?
Make it accelerate
Which force increases when the surface area of an object moving through air increases?
Air resistance
What are the units for mass and weight?
Mass-G Weight-N
Why does a book lying on a table remain at rest?
Because the forces acting on it are balanced
If you had two objects, one that has a weight of 60 N and the other with a weight of 30 N, does gravitational acceleration differ for both objects?
No, it does not differ for either object as the pull of gravity stays the same.
What is the unit for force?
N
Which force is reduced when a surface is made smoother?
Friction
True or false: mass and weight are inversely proportional.
False
What does Newton's Second Law of Motion state?
The force acting on an object is equal to the mass of the object multiplied by its acceleration.
A falling object reaches terminal velocity after 10 seconds. What does this tell you about the net force acting on it after 10 seconds?
It is zero as air resistance equals gravitational pull which results in constant speed.