FORCES

Question 1

What do vector quantities have

Answer 1

magnitude and a direction

Question 2

examples of vector quantities

Answer 2

velocity
acceleration
momentum

Question 3

what do scalar quantities have

Answer 3

magnitude

Question 4

examples of scalar quantities

Answer 4

speed
distance

time

Question 5

what is a contact force

Answer 5

when two objects are touching for a force to act

Question 6

examples of a contact force

Answer 6

friction
air resistance
tension in ropes
normal contact forces

Question 7

what is a non contact force

Answer 7

if the objects do not need to be touching for a force to act

Question 8

examples of a non contact force

Answer 8

magnetic force
gravitational force
electrostatic force

Question 9

what is gravitational force

Answer 9

is the force of attraction between masses

Question 10

what does the weight of an object depend on

Answer 10

the strength of the gravitational field at the location of the object

Question 11

mass and weight are …..

Answer 11

directly proportional

Question 12

weight =

Answer 12

mass * gravitational field strength

Question 13

increasing the mass of an object increases the ….

Answer 13

weight

Question 14

what is resultant force

Answer 14

is the overall force on a point or an object

Question 15

when a force moves an object through a distance what happens

Answer 15

energy is transferred and work is done on the object

Question 16

work done =

Answer 16

force * distance

Question 17

when all forces are balanced an object is

Answer 17

equilibrium

Question 18

what diagram can you draw to find out resultant forces

Answer 18

scale drawings

Question 19

extension is __________ force

Answer 19

directly proportional

Question 20

force= (springs) units

Answer 20

spring constant (n/m) * extension (m)

Question 21

what does spring constant depend on

Answer 21

the material

the stiffer the materal the greater the spring constant

Question 22

what happens when a graph showing force and extension curves (spring)

Answer 22

it has reached its limit of proportionality

Question 23

elastic potential energy =

Answer 23

1/2 * spring constant (n/m) * extension (m) (squared)

Question 24

what is a moment

Answer 24

a moment is the turning effect of a force

Question 25

moment of a force=

Answer 25

force * distance

Question 26

how do you get the maximum moment

Answer 26

need to push at right angles

Question 27

what are levers

Answer 27

levers increase the distance from the pivot at which the force is applied

Question 28

what do levers make it easier to do

Answer 28

makes it easier to work

Question 29

what are gears used for

Answer 29

they are used to transmit the rotational effect of a force from one place to another

Question 30

what are different size gears used for

Answer 30

they can be used to change the moment of a force

Question 31

pressure =

Answer 31

force/area

Question 32

what does pressure in a liquid depend on

Answer 32

depth | density

Question 33

the more dense a liquid is ….. which means....

Answer 33

the more particles in a certain space,, which means there are more particles available to collide s the pressure is higher

Question 34

as the depth of liquid increases ….

Answer 34

the number of particles above that point increases, the weight of these particles adds to the pressure felt at that point so liquid pressure increases with depth

Question 35

pressure = (depth)

Answer 35

height* gravitational field * density of a liquid

Question 36

how does an object float

Answer 36

if the upthrust on an object is equal to the object weight then the forces balance and the object floats

Question 37

how does an object sink

Answer 37

if an object weight is more than the upthrust the object sinks

Question 38

what happens when an object is denser than the fluid it is placed iin

Answer 38

the object is unable to displace enough fluid to equal its weight this means that its weight is always larger than the upthrust so it sinks

Question 39

what is distance

Answer 39

how far an object has moved

Question 40

is distance a scalar or a vector

Answer 40

scalar

Question 41

is displacement a scalar or a vector

Answer 41

vector

Question 42

speed =

Answer 42

distance/ time

Question 43

what is acceleration

Answer 43

acceleration is the change in velocity in a certain amount of time

Question 44

average accerleration =

Answer 44

change in velocity/time

Question 45

what is constant acceleration also called

Answer 45

uniform accleration

Question 46

equation for uniform acceleration

Answer 46

v2-u2=2as final velocity-initial velocity = 2 * accerleration * distance

Question 47

distance time graphs gradient=

Answer 47

speed

Question 48

flat sections on a distance time graph =

Answer 48

stationary it has stopped

Question 49

straight uphill sections on a distance time graphs =

Answer 49

travelling at a steady speed

Question 50

curves represent on a dt graph

Answer 50

accerlerATION OR DECERLAERATION

Question 51

WHAT DOES A STEEPENIGN curve represent | what does a levelling odf== curve reoprestn

Answer 51

speeding up | slowing down

Question 52

on a vt graph gradient =

Answer 52

acceleration

Question 53

on a vt graph flat sections represent

Answer 53

travelling at a steady speed

Question 54

the steeper the vt graph

Answer 54

the greater the acceleration or deceleration

Question 55

uphill sections on a vt graph are | dowbhill sections on a vt graph are

Answer 55

acceleration | deceleration

Question 56

what deos a curve mean on a vt graph

Answer 56

changing acceleration

Question 57

hoe do you work out distance travelled on a vt graph

Answer 57

calculate the area under the graph

Question 58

drag increases as ….

Answer 58

speed increases

Question 59

friction always acts in the …..

Answer 59

opposite direction to movement

Question 60

how do objects reach terminal velocity

Answer 60

as the object falls it accelerates towards the earth due to the force of gravity air resistance also acts on the object in the opposite direction to the force due to gravity as the object speeds up the air resistance increases until the accelerating force and the air resistance balance it has reach terminal velocity