science test: oct 30th

Question 1

what is a simple machine?

Answer 1

anything that reduces or changes the direction of the force that must be applied to move any object.

Question 2

what are the 6 simple machines?

Answer 2

• inclined plane (ramp)
• wedge
• screw
• lever
• wheel and axle
• pulley

Question 3

what is an inclined plane?

Answer 3

a tilted flat surface ex. ramp.

Question 4

how do we use it?

Answer 4

wheelchair access.

Question 5

what is a wedge?

Answer 5

a modified incline plane that can be moved with force

Question 6

what is an example and what is a description of what it does? (wedge)

Answer 6

ex. knife, it cuts food.

Question 7

what is a screw (Archimedes) screw?

Answer 7

an incline plane that can be cut into a central core.

Question 8

what is an example and what is a description of what it does? (archimedes screw)

Answer 8

ex. a screw, it holds things together.

Question 9

what is a lever?

Answer 9

a lever is a rigid bar that pivots at a point called ‘fulcrum’ -

Question 10

what is an effort arm?

Answer 10

part of bar between the fulcrum and where the effort is applied.

Question 11

what is a load arm?

Answer 11

a load arm is the section between fulcrum and object you want to move.

Question 12

what is the first class of levers?

Answer 12

fulcrum between the load core and input force ex. teeter totter

Question 13

what is the second class of levers?

Answer 13

load force (dirt) is between the fulcrum and the input force (person) ex. wheel barrow

Question 14

what is the third class of levers?

Answer 14

input force (lifting the fish pole) is between fulcrum (person) and the load force (fish)

Question 15

what is an example of a wheel and axel- gear?

Answer 15

doorknob -
wheel = doorknob
axel = shaft
turning motion is transferred to another part of the system, making the work easier
ex well (turning the handle raises the bucket)

Question 16

what does a pulley have to do with wheels and axels???

Answer 16

uses wheels and axels to make lifting/moving large heavy objects easier, more pulleys easier the task.

Question 17

what is a force?

Answer 17

a force is a push or pull upon an object resulting from the objects interaction with another object. whenever there is an interacting between two objects, there is a force upon each of the objects. when the interaction ceases, the two objects no longer experience the force. forces ONLY exist as a result of an interaction.

Question 18

what are the 8 types of forces?

Answer 18

gravitational, magnetic, electrical (aka electricity), mechanical force, frictional (aka tensile), compressive, rotational.

Question 19

what is gravitational force?

Answer 19

pull of the earth downward an object, everything falls at same rate if there was no resistance 9.8 m/s.

Question 20

what is a magnetic force?

Answer 20

magnetic push (north to north, south to south) or pull (north to south, south to north.

Question 21

what is an electrical force?

Answer 21

static cling, static electricity, electric current, lightning.

Question 22

what is a mechanical force?

Answer 22

muscular, hurricane, punch, slapshot, rubbing, abrasion, resistance.

Question 23

what is a tensile force?

Answer 23

tightening.

Question 24

what is a compressive force?

Answer 24

crushing, squeezing, grip.

Question 25

what is rotational force?

Answer 25

twist, turn, wiring, coil.

Question 26

**what 2 components do all forces have?

Answer 26

magnitude - how strong the force is
direction - which way the force is pushing/pulling

Question 27

tip: in diagrams the arrow represents the direction while the length and thing represents the magnitude.

Answer 27

if you wanna be valedictorian, get your grades up…

Question 28

the unit we used to measure force is called…

Answer 28

NEWTON (N), is named after Isaac Newton.

Question 29

what is mass?

Answer 29

measure of the amount of matter in a object.

Question 30

what is weight?

Answer 30

measure of how strong the force of gravity between 2 objects.

Question 31

what is friction?

Answer 31

a force that resists motion between 2 objects in contact with each other.

Question 32

what is static fraction?

Answer 32

the force that prevents surface at rest from sliding against each other.

Question 33

what is sliding friction?

Answer 33

the force that acts against the movement and causes objects to slow and eventually stop.

Question 34

what is a lubricant?

Answer 34

a substance that reduces friction and helps objects slide more easily.

Question 35

what is a mechanical advange?

Answer 35

the benefits of using a machine expressed as a number that compares input to output.

Question 36

what is an ideal mechanical advantage?

Answer 36

what should happen according to the calculations.

Question 37

what is the formula when using a lever (stationary objects)?

Answer 37

M.A (mechanical advantage) = effort arm/ length load arm length.

Question 38

what is the formula when using an object (usually pulley related)?

Answer 38

M.A (mechanical advantage) = input distance/output distance

Question 39

what is an input distance?

Answer 39

the distance over which the distance is applied.

Question 40

what is an output distance?

Answer 40

how far the load moves.