Chapter 2: Describing Objects in Linear Motion

Question 1

What branch of rigid-body mechanics is concerned with the mechanics of moving objects

Answer 1

Dynamics

Question 2

What branch of dynamics is concerned with the description of motion (ie speed, velocity)

Answer 2

Kinematics

Question 3

What type of motion do all points on the body move?
-same distance, same direction, at the same time

Answer 3

Linear motion (translation)

Question 4

What type of motion is a staight line?
Ex: figure skater gliding across the ice

Answer 4

Rectilinear translation

Question 5

What type of motion is a curved line?
Ex: Ski jumper during “jump” phase

Answer 5

Curvilinear translation

Question 6

For both rectilinear and curvilinear translation, all points on a body/object move so that orientation of the object does not change and ALL points on the object move the same distance-The difference is the ___

Answer 6

Line (curved vs straight)

Question 7

What type of motion (rotation) do all points on the body move through the same angle
-all points on body or object move in circles (or parts of circles) about the same fixed central line or axis

Answer 7

Angular motion (rotation)

Question 7

A type of angular motion that is a giant swing or pirouette

Answer 7

Whole body rotation

Question 8

What type of angular motion involved flexion, extension, adduction, abduction

Answer 8

Segment rotation

Question 8

What type of motion combines angular and linear motion?
-Most common in sports and human movement, like peddling a bike or walking

Answer 8

General motion (mixed)

Question 9

The 4 descriptors of linear motion

Answer 9

How far?
What direction?
How fast?
Speeding up, slowing down?

Question 10

Term used to describe something identifying location in space

Answer 10

Position

Question 11

A position that consists of starting line and finish line (+40m, -40m)

Answer 11

1 dimension

Question 12

A position that consists of a goal line, sideline and Cartesian coordinate system

Answer 12

2 dimensions

Question 13

A position that consists of ball on tennis court from baseline, from sideline, how high

Answer 13

3 dimensions

Question 14

Both ____ and ____ measure a change in position (motion)

Answer 14

Distance and Displacement

Question 15

What is the term used to describe the length of path traveled

Answer 15

Distance (scaler)

Question 16

What term uses a vector (a number and direction), linear distance in a specified direction

Answer 16

Displacement

Question 17

Which way is x-direction?

Answer 17

Horizontal

Question 18

Which way is y-direction?

Answer 18

Vertical

Question 19

What is a straight line between initial (start) and final (end)

Answer 19

Resultant

Question 20

Both ____ and _____ measure rate of motion
-How fast the body is moving (meters/second=m/s)

Answer 20

Speed and Velocity

Question 21

Equation for Speed (scalar) length of space traveled

Answer 21

speed= distance traveled (meters) / time taken (seconds)

Question 22

Equation for Velocity (vector)

Answer 22

velocity= displacement (meters)/time taken (seconds)

Question 23

____is rate of motion, _____is rate of motion in a ____ direction

Answer 23

Speed, velocity, specific

Question 24

Rate of motion at an instant in time
-time duration very short
-change in position very short (interval of a race)

Answer 24

Instantaneous Speed or Velocity

Question 25

Formula for average velocity

Answer 25

v= d/ change in t (or time taken)

Question 26

Rate of change in velocity
-starts, stops, speeds up, slows down, changes direction

Answer 26

Acceleration

Question 27

What type of acceleration is best described as: when acceleration is constant (constant force)
-allows for prediction of future position and velocity
-two many applications (vertical and horizontal motion)

Answer 27

Uniform acceleration

Question 28

Two types of uniform acceleration: ____ and ____

Answer 28

Vertical motion and horizontal motion

Question 29

____motion: gravitational force constant
a=g=-9.81 m/s squared (- downward)

Answer 29

Vertical motion

Question 30

____motion: ignore air resistance
acceleration= 0 m/s squared

Answer 30

Horizontal motion

Question 31

Vi and Vf describe what

Answer 31

initial velocity and final velocity

Question 32

change in y describes what?
yi=_____
yf=____

Answer 32

y displacement
yi= initial position
yf= final position

Question 33

g stands for what and what is the numerical part of this?

Answer 33

gravitational acceleration= -9.81 m/s squared

Question 34

change in time describes what?
ti= ___
tf=___

Answer 34

time interval
ti= time interval
tf= time final

Question 35

Formula for vertical velocity at the end of some time interval

Answer 35

vf=vi + g*change in time

Question 36

Formula for vertical position at the end of some time interval

Answer 36

yf=yi+vi change in t +1/2g*(change in time)squared

Question 37

Formula for calculating velocity at the end of some displacemnt (s)

Answer 37

vf squared= v initial squared + 2g* change in y

Question 38

True or false: Horizontal velocity remains constant over time

Answer 38

True

Question 39

True or false: Horizontal displacement depends only on time interval

Answer 39

True

Question 40

True or false: Horizontal velocity remains constant over a displacement

Answer 40

True

Question 41

A type of motion that describes: An object in the air acted on only by forces of gravity and air resistance
-Consider vertical and horizontal kinematics separately
-Apply appropriate equation of uniform acceleration for each direction

Answer 41

Projectile motion

Question 42

Type of motion that describes a plane curve that mirrors symmetrical and U-shaped

Answer 42

Parabola