Forces paper 2

Question 1

What is a scalar?

Answer 1

physical quantities that only have magnitude(size)

Question 2

What is an example of a scalar?

Answer 2

Distance
speed
mass
time
3Km

Question 3

what is a vector?

Answer 3

physical quantity that has both a magnitude and a direction

Question 4

examples of vectors

Answer 4

force
displacement
momentum
velocity

Question 5

What is resultant force

Answer 5

A single force that replaces all forces acting on an object

Question 6

How do you draw vectors

Answer 6

lenghth of arrow= magnitude
way it’s pointing = direction

Question 7

Explain how a car travels at constant speed?

Answer 7

The cars toward force is equal to the total resultant force and therefore has reached equilibrium

Question 8

What is displacement

Answer 8

The independent route taken rather from start to end

Question 9

What is equilibrium

Answer 9

when the forces acting on an object are balenced

Question 10

what is force

Answer 10

non contact or contact way of affecting an object e.g push or pull

Question 11

what is weight

Answer 11

measure of force

Question 12

what is mass

Answer 12

measure of how much matter is in an object

Question 13

what is the equation that links weight mass and gravitational field strength

Answer 13

weight = mass x gravitational field strength

weight = N
mass = Kg
gfs= N/Kg

Question 14

what are some examples of a contact force

Answer 14

friction
air resistance
tension(pulling force)
BOTH OBJECTS EXPERINCE SAME SIZE FORCE BUT IN OPPOSITE DIRECTIONS

Question 15

examples of non contact forces

Answer 15

gravitational force
magnetic (either attractive or repulsive)
electrostatic

Question 16

what happens to strength of the force as objects get pulled further apart

Answer 16

decreases

Question 17

equation that links work done force and distance

Answer 17

work done = force x distance
N/m N. m

Question 18

what’s a key feature of liquids

Answer 18

virtually incompressible as the particles are close together therefore allow no movement

Question 19

what can happen to an object if u apply force to it

Answer 19

compress
stretch
bend

Question 20

how do objects float

Answer 20

if the weight of then object EQUALS the upthrust

Question 21

what happens if moments balence

Answer 21

there will be no turning point

Question 22

What is plastic deformation

Answer 22

when an object can’t return to its original shape

Question 23

what’s elastic deformation

Answer 23

when an object CAN return to its original shape

Question 24

what’s extension

Answer 24

the increase in length of a spring when it’s stretched

Question 25

how many forces act on an object

Answer 25

always more than one

Question 26

equation that links force spring constant and extension

Answer 26

force= spring constant x extension N. N/m. m

Question 27

what is spring constant

Answer 27

how many newtons it would take to stretch the object by 1m

Question 28

what is hookes law

Answer 28

the extension of a stretched spring is directly proportional to force applied

Question 29

what is the region called on a graph when it DOES obey hookes law

Answer 29

elastic region

Question 30

what is the point called when the graph stops obeying hookes law

Answer 30

elastic limit

Question 31

what’s the region called when Hookes law does NOT apply

Answer 31

plastic region

Question 32

what’s a moment

Answer 32

rotational or turning effect of a force

Question 33

how do u calculate moment

Answer 33

force x distance N. m

Question 34

INFO the distance is the perpendicular distance from the pivot. The force is applied at right angles

Question 35

how does an object become balenced

Answer 35

the total clockwise monument is equal to total anticlockwise moment about a pivot

Question 36

INFO smaller mass needs a longer distance to balence a bigger mass as it produces a smaller force

Question 37

what is a gear

Answer 37

transmit the turning effect of a force

Question 38

INFO

Answer 38

The motion output at the driven shaft will be diffrent from the motion input at the driver shaft

Question 39

will a smaller gear create smaller or bigger moments

Answer 39

smaller

Question 40

does a small gear or big gear turn quicker

Answer 40

small

Question 41

Do gears turn in same direction

Answer 41

No

Question 42

What is the gear ratio?

Answer 42

number of teeth ok driven gear over number of teeth on driver gear

Question 43

What are levers

Answer 43

an object that makes it easier to do work e.g lift a load

Question 44

How do you make it easier to lift a load

Answer 44

Increase distance between pivot and applied force Less force required to get the same moment easier to lift load

Question 45

what’s the genral formula for pressure

Answer 45

pressure = force over area (m)squared

Question 46

what is a fluid

Answer 46

liquid or gas

Question 47

how does a gas create pressure

Answer 47

the particles collide with the walls of the container creating pressure(applies a force)

Question 48

how does a liquid create pressure

Answer 48

water particles collide with walls and air. Exerts pressure outwards in every direction

Question 49

Does a more dense liquid have higher pressure

Answer 49

yes

Question 50

will a less dense liquid have lower pressure

Answer 50

yes

Question 51

as depth increases what happens

Answer 51

higher pressure

Question 52

Why does the pressure increase as you go further down

Answer 52

the weight of the water at the bottom of the container is pushed by the water further up

Question 53

denser the liquid…..

Answer 53

larger mass per unit of vol

Question 54

how do you work out pressure in coloum of fluid

Answer 54

pressure= phg (density x height x gfs) density = kg/m3 height = m gfs= N/ Kg

Question 55

what is upthrust

Answer 55

resultant force acting on an object due to higher pressure at the bottom of the liquid than on top

Question 56

Will a more dense object float or sink

Answer 56

sink

Question 57

what do you always have to do at the end of calculating pressure

Answer 57

ADD ATMOSPHERIC PRESSURE

Question 58

Why does atmospheric pressure decrease with increasing altitude

Answer 58

increasing altitudes there are fewer air molecules number of collisions with surface decrease less weight of air than below the surface

Question 59

why do airplanes window have this shape?

Answer 59

force form air pressure acting form inside to outside bigger than force acting inwards keeps window in position