Displacement and Position-Time Graphs Test

Question 1

Mechanics

Answer 1

the study of motion

Question 2

Kinematics

Answer 2

the science describing the motion of objects using words, diagrams, numbers, graphs and equations

Question 3

What does kinematics allow us to do?

Answer 3

ultimately develop sophisticated mental models that serve to describe and ultimately explain the motion of real world objects

Question 4

What are the 3 ways motion can be described by?

Answer 4

1. A reference point
2. A magnitude (number and unit)
3. A direction

as well as certain physical characteristics such as SPEED, DISTANCE, TIME, VELOCITY, ACCELERATION etc

Question 5

Characteristics and Examples of Scalar Quantities

Answer 5

-only have a size and unit

2 Parts:

1. Number
2. Unit

Examples:
Distance (d) - 5m
Speed (v) - 15km/hr
Time (t) -8.0s

Question 6

Characteristics and Examples of Vector Quantities

Answer 6

-have a size, unit AND direction

3 Parts:

1. Number
2. Unit
3. Direction

Examples:
Displacement (∆d) - 5m [E]
Velocity (v) - 15km/hr [NW]
Acceleration (a) - 8m/s [FORWARD]

Question 7

Position

Answer 7

the location of an object relative to a reference point (a vector quantity)

—> includes magnitude, direction, and a reference point
EX. 15m [N] of the school

Question 8

Displacement

Answer 8

the change in position from a reference point (a vector quantity)

—> includes magnitude, and direction
EX. 15m [N] of some starting point

Question 9

Displacement Formula

Answer 9

∆d = d2 - d1

Question 10

Change in:
Vector:
Final position:
Initial position:

Answer 10

∆
d
d2
d1

Question 11

When would you use the subtracting displacement formula?

∆d = d2 - d1

Answer 11

when there is 1 displacement
(when the vectors follow the same direction)

EX. both vectors are going [E]
———————>——–>

Question 12

When would you use the adding displacement formula?

∆d = ∆d1 + ∆d2

Answer 12

when there is more than 1 displacement
(when vectors are in different directions)

Ex one vector going [W] then another traveling [E] from that last point

Question 13

Distance

Answer 13

the length of a path taken (scalar quantity)

—> includes magnitude only
EX. 15 km

Question 14

Positive Sign Conventions

Answer 14

East [E]
Right [R]
North [N]
Up

Question 15

Negative Sign Conventions

Answer 15

West [W]
Left [L]
South [S]
Down

Question 16

Vector Drawing Rules

Answer 16

1. The vector is drawn pointing in the direction of the vector
   - ———> 10km [E]
2. The length is proportional to the magnitude of the measurement
   (20km is 2x longer than 10km so the vector should be too)
   ———-> 10km/hr 20km/hr

Question 17

Colinear Vectors

Answer 17

vectors that lie along the same line

• only colinear vectors add or subtract like ordinary numbers or scalars
• vectors are also colinear if they lie along a straight line in opposite directions

Question 18

Position-Time Graphs

Answer 18

a position-time graph gives a visual representation of the motion of an object

Question 19

Uniform Motion

Answer 19

motion with no change in direction

Question 20

Straight Line on a position-time graph means?

Answer 20

an object is moving through equal displacement in equal time intervals (constant rate)

Question 21

Horizontal Line on a position-time graph means?

Answer 21

the object is stationary as the position does not change with time

Question 22

Velocity

Answer 22

the change in distance per time unit

EX. m/s or km/hr

Question 23

To Calculate Velocity:

Answer 23

look at the slope of a position-time graph for an object in uniform motion

slope =
y2 - y1
———–
x2 - x1

Question 24

Formula For AVERAGE VELOCITY:

average velocity =
displacement
———————
time taken

Answer 24

any “d” is the y-coordinate of a point from the beginning or end of a line

Vave =
df - di
——–
tf - ti

∆t

Question 25

velocity can be positive or negative

—> moving in the positive or negative direction

Answer 25

in other words, the objects movement can be towards or away from the origin

Question 26

Average Velocity Between 2 Points:

Answer 26

the average velocity between any 2 points on a position time graph is equal to the slope of the line drawn between the 2 points

Question 27

Significant Digit Rules For Adding & Subtracting

Answer 27

round the sum or difference so that it has the same number of decimals places as the measurement HAVING THE FEWEST DECIMAL PLACES

Question 28

Significant Digit Rules For Multiplying & Dividing

Answer 28

express the product or quotient to the same number of significant digits as the multiplied or divided number HAVING THE LEAST NUMBER OF SIGNIFICANT DIGITS

Question 29

Conversion to get a smaller answer:

m —> km

Answer 29

x and y equal whatever unit of measure the question pertains to

(1/x) multiplied by (1/y)

Question 30

Conversion to get a larger answer:

km —> m

Answer 30

x and y equal whatever unit of measure the question pertains to

(x/1) multiplied by (y/1)