Motion

Question 1

What is the study of kinematics

Answer 1

Study of causes of motion and changes in motion

Question 2

What are the 2 types of quatities

Answer 2

Scalar: have magnitude but no direction
Vector: Have magnitude and direction

Question 3

What is a displacement and how is it measured

Answer 3

A displacement is the magnitude and direction of an objects change in location
Measured in m or km with direction in [ ] (150m [E])

Question 4

How do you measure velocity?

Answer 4

Velocity is the change in position with respect to time

v=(∆d/∆t)

Question 5

What is a motion graph?

Answer 5

Graphs the motion of an object based on position and time

Question 6

What is a velocity-time graph?

Answer 6

Graphs velocity with respect to time
Total displacement = total area
When velocity is constant, displacement is v*t

Question 7

What is Newtons first law of motion?

Answer 7

An object in motion will stay in motion unless acted upon by an external force and an object at rest will remain at rest until acted on by an external force.
Seatbelts were designed to stop a person in motion when a car suddenly stops (person would otherwise continue moving at a high speed into their windshield)

Question 8

Define a force

Answer 8

A push or pull that results in the change in velocity of an object
Has both magnitude and direction (is a vector quantity
Measured in Newtons (N)

Question 9

What is acceleration

Answer 9

Change in velocity over change in time

a = (∆v/∆t)

Question 10

How do you find total displacement using a velocity time graph?

Answer 10

Graph will make a triangle when acceleration is constant
Area of a triangle is (1/2 of base)*height
Area = displacement

Question 11

How do you find average velocity when given displacement

Answer 11

∆d/∆t

Question 12

How is acceleration calculated?

Answer 12

acceleration is the change in velocity over the change in time
∆v/∆t ((v2-v1)/∆t)

Question 13

What is Newtons second law of motion?

Answer 13

If the net force on an object is not zero, it will accelerate in the direction of the net force. The acceleration is directly proportional to the net force and inversely proportional to the mass.
Acceleration = net force/mass
Often written as Net force = acceleration*mass

Question 14

How do you calculate net force?

Answer 14

Net force = mass (in kg)acceleration
Measured in Newtons
1N = 1kg1m/s^2

Question 15

How do you draw a free body diagram?

Answer 15

FBD is drawn by making a box to represent the object in question and drawing the forces acting upon it in one of 4 directions; up, down, left or right.
The size of the arrow dictates the madnitide of the force

Question 16

What are possible forces acting in an FBD

Answer 16

Gravity Fg (always points downward)
normal force FN (solid surface negating gravity, always points up
applied force Fa (pushing the object)
force of tension (pulling the object)
Frictions
- Fs = static, active only when an object is moving, prevents objects from sliding
- Fk = Kinetic friction, acts opposite to the velocity of an object
Air friction: drag

Question 17

What is Newtons third law?

Answer 17

For every action force, there is a reaction force equal in magnitude but opposite in direction

Question 18

What is the force of gravity (rough estimate)

Answer 18

9.8m/s^2 down