Lesson 1 - Forces
A force is defined as a _______ or ________.
a push or pull
Mr. Hall going down the slide on the playground is an example of which type of friction?
Sliding friction
Newton's first law states: an object at rest will stay at _______ unless acted on by an outside force.
An object in motion will stay in ____________ unless acted on by an outside force.
rest; motion
What is the difference between speed and velocity?
They are the same measurement, except velocity has a direction.
Force is measured in...
Newtons (N)
The combination of all forces that act on an object is know as...
net force
The force that two surfaces exert on each other when they rub against each other is called...
friction
The fact that it's easier to push an empty shopping cart than it is to push a full shopping cart is an example of which of Newton's Laws?
If momentum (P) = mv, what is the momentum of a 200 kg bowling ball moving towards the pins at 10 m/s?
2000 kgm/s
This for a force that pulls objects down / towards each other.
Gravity
Braelyn pushes a chair to the right towards Olive with 50 N of force. Olive pushes back with 55 N of force. What is the net force on the chair?
5 Newtons to the left
If Mrs. Culver were to push a rolling cart down the hallway to deliver coffee to the teachers, this would be an example of which type of friction?
Rolling friction
Free fall is acceleration caused by __________.
Gravity
This is the constant measurement of gravity...
9.8 m/s2
When the net force on an object equals 0N, then the forces are...
balanced
Mr. Garrity throws an expo marker at Mrs. Barry from across the room. Which type of friction comes into play, here?
Fluid friction
Newton's second law states: F=MA. What does each letter stand for?
F = force
M = mass
A = acceleration
In order to calculate free fall, you use the equation
v=gt. What is the free fall of a ball that drops from the top of a building in 5 seconds?
49 m/s
The resistance to a change in motion is also known as...
Inertia
Lila pulls a desk towards herself with 100 N of force. Olivia pushes the desk towards Lila with an additional 25 N of force. Anna decides to jump in an help push the desk towards Lila with an additional 50 N of force. What is the net force on the desk?
175 N towards Lila
Pepper likes to sit still on the skull in her tank. This is an example of which type of friction?
Static friction
equal; opposite
Calculate the momentum of a car that is moving at 100 m/s and has a mass of 50 kg?
5000 kgm/s
Explain the difference between mass and weight.
Mass is the amount of matter in an object and generally does not change.
Weight is the measure of the force of gravity on an object and can change based on how strong gravitational forces are.