May the Net Force Be With You
The sum of all the forces acting on an object.
What is net force?
This is the force that opposes the sliding motion of two surfaces that are touching each other. e.g. rock rolling down a hill
What is friction?
What is the force that keeps planets in their orbits?
Gravity
The tendency of an object to resist any change in its motion. Also called Newton's First Law of Motion
What is inertia?
What is the force on a 2 kg object accelerating at 3 m/s?
What 6 N?
This happens to the motion (direction) of an object when you exert a force on it.
The motion of the object will change?
Name two types of contact forces
friction, normal, applied, spring, tension, air resistance
Weight (in Science) calculated in ________
Newtons (N)
It is easier to push a 40kg ball than a 400kg ball. This is an example of Newton’s _____________
Second Law of Motion
Daily Double - A 2 kg object increases its velocity from 3 m/s to 15 m/s in 4 seconds. Find acceleration and force.
a = 3 m/s2
F = 6 N
This occurs when students are pushing on an object e.g. a door, in opposite directions, with the same size force.
What is a balanced force?
Name a field force
gravity, magnetic, strong or weak nuclear
The gravitational force exerted on an object is this. This quantity will change depending on where you are in the solar system.
What is weight?
A ball rolling down a hill will continue to roll unless friction or another force stops it. This is an example of Newton’s _____________
First Law of Motion
A 70 kg astronaut is on the moon. (g = 1.6 m/s2) What is their weight?
W = 112 N
This occurs during an unbalanced force.
The object moves
Friction always acts______________ the direction of motion of an object.
A. opposite to
B. in the same direction as
C. perpendicular to
A. Opposite
If you were no longer on Earth, ________ would remain the same, however _________ would change with gravity.
What are: mass and weight
(For the quiz, learn the diff between Mass and Weight)
To calculate the force an object exerts, you use this formula.
What is F = ma?
Which law describes what happens when a tablecloth is pulled out from under a setting of china without damaging it?
First Law of Motion
Name the three variables that are related to Newton's 2nd Law of Motion.
Force, mass, and acceleration
Gravity is a force that acts in which direction?
downward
What is the acceleration due to gravity on earth?
9.8 m/s2
Releasing a balloon full of air causes it to fly around the room as the gas released from inside propels the balloon through the air. This is an example of Newton’s ________________.
Third Law of Motion
Two objects have the same force applied. Object A has a mass of 2 kg and object B has a mass of 8 kg. Which object accelerates more?
Object A will accelerate more because it has less mass.