UNIT ONE: MOTION IN A STRAIGHT LINE

Question 1

What is displacement?

Answer 1

Displacement is change in position and is a vector quantity.

Question 2

What is motion?

Answer 2

Motion is change in an object’s location as measured by the observer

Question 3

What is distance?

Answer 3

The total length of the path travelled by an object in motion. It is a scalar quantity.

Question 4

What is direction?

Answer 4

The line an object moves along from an origin point.

Question 5

What is a scalar quantity?

Answer 5

Scalar quantities are measurements that only have a magnitude. Magnitudes represent size, not but directio.

Question 6

What is a vector?

Answer 6

Vector is a quantity that has BOTH magnitude and direction.

Question 7

What is position?

Answer 7

Position is the distance and direction of an object from a specific reference point. Position is a vector quantity.

Question 8

What is this formula for?

Answer 8

displacement.

final position - initial position

Question 9

When an object changes position more than once, the total displacement can be calculated how?

Answer 9

Adding the displacements together.

Question 10

If you left home, travelled to school, then to work, what is your distance?

Answer 10

2000m

Question 11

If you left home, went to school, the library, work and came home at the end of the day, what is your displacement?

Answer 11

displacement = final position - initial position

displacement is zero.

You ended where you started.

Question 12

What is each line called?

Answer 12

a. line segment
b. directed line segment.
c. directed line segment.

Question 13

Define average speed

Answer 13

Average speed (V_av) is the total distance travelled divided by the total time taken to travel that distance

ex. A car travelled 50km, and it took an hour to get to it’s destination.

50km divided by 60mins

= 50km/hour

Question 14

What is average velocity?

Answer 14

Average velocity is the total change in position divided by the total time for that displacement.

Question 15

A position-time graph describes the ________ of an object, with ______ on the vertical axis and _______ on the horizontal axis

Answer 15

A position-time graph describes the motion of an object, with position on the vertical axis and the time on the horizontal axis

Question 16

The slope of a position-time graph gives us

Answer 16

the velocity of an object.

Question 17

Which graph can determine the average velocity with the information it contains?

Answer 17

Position-time graph

Question 18

Motion of an object at a constant speed AND in a straight line is called ____________

Answer 18

Motion of an object at a constant speed AND in a straight line is called motion with uniform / constant velocity

Question 19

Motion in which the object’s speed changes or the object does not travel in a straight line is ______________

Answer 19

Motion in which the object’s speed changes or the object does not travel in a straight line is motion with non-uniform velocity (accelerated motion)

Question 20

How would the position-time graph look, given the type of motion:

Answer 20

Question 21

Given the type of motion, how would the position-time graph look?

Answer 21

Question 22

Given the type of motion below, how would the graph look?

Answer 22

Question 23

Given the type of motion, what does the position-time graph look like and what does it represent?

Answer 23

Constant positive velocity

Question 24

Given the following types of motion, what does the position-time graph look like and what does it represent?

Answer 24

Straight line, represents constant velocity

Question 25

How quickly the change in velocity of an object describes \_\_\_\_\_\_\_\_\_\_\_\_\_\_

Answer 25

How quickly the change in velocity of an object describes **acceleration.**

Question 26

A graph describing the motion of an object, with **uniform velocity or uniform accerlation** is called? What is on the vertical axis, what is on the horizontal axis?

Answer 26

A velocity-time graph with velocity on the vertical axis and time on the horizontal.

Question 27

What are some characteristics of the type of motion this position-time graph?

Answer 27

* object is speeding up in a positive direction. * it is not constant, shows acceleration

Question 28

Is this object slowing down or speeding up? Is velocity constant?

Answer 28

It is speeding up in a negative direction (west) and the velocity is not constant since the line is curved showing change.

Question 29

Is the object increasing in speed or slowing down? How do you know?

Answer 29

The object is slowing down, moving in a positive direction. It is slowing down because the slope of the curve is decreasing.

Question 30

Given the motion type, what does the position-time graph look like?

Answer 30

Question 31

The slope of a velocity-time graph gives the ____________ of the object.

Answer 31

The slope of a velocity-time graph gives the **acceleration** of the object.

Question 32

The area under the velocity-time graph gives the ___________ of the object.

Answer 32

The area under the velocity-time graph gives the **displacement** of the object.

Question 33

What does this equation describe?

Answer 33

Average acceleration

Question 34

Answer 34

slope.

Question 35

What is the SI unit for acceleration?

Answer 35

m/s²

Question 36

Motion with uniform acceleration:

Answer 36

is motion in which velocity changes at a constant rate.

Question 37

Instaneous velocity is the velocity of an object at a _____________ in time

Answer 37

Instaneous velocity is the velocity of an object at a **specific instant** in time

Question 38

A graph describing motion of an object, with acceleration on the vertical axis and time on the horizontal axis is called:

Answer 38

an acceleration-time graph image shows uniform acceleration

Question 39

The area under an acceleration-time graph determines \_\_\_\_\_\_\_\_\_\_

Answer 39

The area under an acceleration-time graph determines **change in velocity**.

Question 40

What type of motion do the three graphs represent?

Answer 40

uniform acceleration.

Question 41

How do you create a velocity-time graph from an acceleration-time graph?

Answer 41

1. calulate area under the curve, break it into different sections where necessary 2. plot points onto chart at various points in time 3. plot data to create the velocity-time graph.

Question 42

How do you create an acceleration-time graph from a velocity-time graph?

Answer 42

1. calculate slope of the line to find acceleration 2. record the acceleration at different points in time 3. use info to plot acceleration at various points in time on a-t graph 4.