Chapter 1: Forces

Question 1

Force

Answer 1

A push or pull exerted by one object, on another object

Question 2

Force pairs are ___in size but act in ___direction on each object

Answer 2

equal, opposite

Question 3

What causes (or tends to cause) an object to accelerate?

Answer 3

start, stop, speed up, slow down, change direction

Question 4

Forces are measured in

Answer 4

SI: Netwon (N) English: pound (lb)

Question 5

The size of push or pull

Answer 5

Magnitude

Question 6

Line of action

Answer 6

Direction

Question 7

Which way a force is pushing or pulling

Answer 7

Sense

Question 8

Where the push or pull is applied on the object

Answer 8

Point of application

Question 9

What 2 quantities does a vector require?

Answer 9

Magnitude and direction

Question 10

True or False? The effect of the forces acting on the body are not affected by changes in the dimensions or shape
ie. hitting a water balloon vs baseball with a baseball bat

Answer 10

True

Question 11

Pair of forces that act WITHIN the object or system
-hold the object together

Answer 11

Internal force

Question 12

Two types of internal force, one pulls (tension) and one squeezes (compression)

Answer 12

Tensile force and compressive force

Question 13

Muscles pull on ____, which pull on____.

Answer 13

tendons, bones

Question 14

Bones push on ____, which pushes on other____ and bone

Answer 14

cartilage

Question 15

A type of force that acts on an object or system through interaction with environment

Answer 15

External force

Question 16

A type of external force where objects touch each other

Answer 16

Contact force

Question 17

A type of external force where objects are not touching each other

Answer 17

Noncontact force

Question 18

A type of external force that is the weight of an object

Answer 18

Gravitational force

Question 19

Force of gravity acting on an object

Answer 19

Weight

Question 20

Formula for Weight

Answer 20

W= m*g
W=weight in newtons
m=mass in kg
g=acceleration due to gravity= 9.81 m/s squared or approx 10m/s squared

Question 21

What is the numerical value for g (acceleration d/t gravity)

Answer 21

9.81 m/s squared downward, or 10 m/s squared

Question 22

True or false, contact forces occur not only when object touch each other, but each force acts separately on one of the objects.
-Also called reaction forces

Answer 22

True

Question 23

A normal contact force is _____ to the two objects in contact

Answer 23

perpendicular

Question 24

A parallel contact force is____to contacting surfaces of two objects
-also known as ___force
-opposes motion or sliding between surfaces

Answer 24

parallel, friction

Question 25

Static friction is when two surfaces are not/are moving on each other

Answer 25

NOT

Question 26

The maximum friction before objects start to slide

Answer 26

Limiting friction

Question 27

Dynamic friction is when two surfaces are/are not moving on each other

Answer 27

ARE

Question 28

Two other names for Dynamic friction

Answer 28

sliding or kinetic friction

Question 29

The great the R (normal reaction force) the greater the ____affected by characteristics of the two materials in contact represented by___.

Answer 29

friction, greek drippy looking u (greek letter mu)

Question 30

Formula for friction

Answer 30

F=uR

Question 31

The sum of all external forces acting on one object -also called resultant force -not simply summing all external force magnitudes, must account for ___of each external force

Answer 31

Net force, direction

Question 32

____ forces is one or more external forces with the same line as action, with identifying one direction as ____ and the opposite direction as _____

Answer 32

Colinear, positive and negative

Question 33

___forces are not colinear but act through the same point. Example of this force: ____

Answer 33

Conccurrent, gymnast hanging from grab bar

Question 34

Formula for concurrent forces

Answer 34

RF squared = HF (net hoizontal force) squared + VF (net vertical force) squared

Question 35

True or false: Sometimes external forses are not colinear and do not act only in the horizontal and vertical directions

Answer 35

Tues