Net Force
What units do we use to measure force?
Newtons (N)
The gravity on Earth is equal to ______ m/s2
The gravity on Earth is equal to 9.8 m/s2
Which law of motion is known as the law of action-reaction?
Third Law of Motion - Every action has an equal and opposite reaction.
What units do we use when measuring momentum?
A force is a _______ or ________ that acts on an object to change its motion.
A force is a PUSH or PULL that acts on an object to change its motion.
What force always acts in the opposite direction of an applied force?
friction
Gravity depends upon _________ and __________
Gravity depends up mass and distance
According to newton's 2nd law of motion, Force = ?
Force = mass x acceleration
What is the equation we use to find the momentum of an object?
Momentum = mass x velocity
When an object is given an initial forward velocity and falls, it will follow a curved path.
Projectile Motion
Net forces that are equal to 0 are considered _______.
Net forces that are equal to 0 are considered BALANCED.
Why does the moon have less gravity than earth?
The moon has less mass.
Which law says that an object in motion will stay in motion while an object at rest will remain at rest, unless acted on by an unbalanced force?
1st Law of Motion
Object A and Object B are rolling on the ground.
What can we infer if Object A has less mass than Object B, but they both have the same momentum?
Object A has greater velocity than Object B
Name the 4 main types of friction.
Static Friction
Sliding Friction
Rolling Friction
Fluid Friction
How could an object have multiple forces acting on it, but not have a change in motion?
if the forces are balanced and cancel each other out.
If you travel to another planet with different gravity than earth, what would change about you?
your weight
Give an example of newton's third law of motion.
answers will vary
What is the momentum of a 2,000 kg truck that is parked. Explain your answer.
Momentum = 0 kg x m/s
Only objects in motion have momentum
What 2 things are needed for a satellite to stay in orbit around earth
gravity
forward velocity / momentum
John, Sarah, and Adam are pulling on a rope but the rope down not move. John pulls to the right with 60 N and Adam pulls to the left with 37 N.
How much force, and in which direction, is Sarah applying to the rope?
Net force = 23 N Left
What is the weight of a 50 kg object on Earth?
weight = 50 kg x 9.8 m/s2 = 490N
According to newton's 2nd law of motion, what are 2 ways to increase the acceleration of an object?
If mass decreases or if force increases
Which object has a greater momentum,
A 2 kg baseball traveling 6.5 m/s OR
a 0.25 kg golf ball traveling 55 m/s?
Baseball's momentum = 13 kg x m/s
golf ball's momentum = 13.75 kg x m/s
The force of air resistance equals the force of gravity. This causes the object to fall at a constant speed.