Physics Paper 1 Flashcards
1
Q
What is a system?
A
An object or a group of objects
2
Q
What happens when a system changes?
A
Energy is transfered
Energy may be transfered: into it, away from it, between different objects in the system pr between different energy stores
3
Q
Give some examples of how energy may be stored when a system changes?
A
An object projected (shot or moved) upward
A moving object hitting an obstical
An object accelerated by a constant force
A vechical slowing down
Briging water to boil in a electric kettle
4
Q
You should be able to use equasions to work out energy in a spring or gravitational potential energy
A
.
5
Q
What is Kinetic energy measured in?
What is it’s symbol
A
J (joules)
Ek (The k is small)
6
Q
What is mass measured in?
What is it’s symbol?
A
Kg
m
7
Q
What is speed measured in?
What is its symbol?
A
m/s
v
8
Q
If you are using the equasion to work out elastic potential energy: what have you assumed?
A
The limit of proportion hasn’t been exceded
9
Q
What is elastic potential energy measured in?
What is its symbol?
A
J joules
Ee (small e)
10
Q
What is the spring constant measured in?
What is its symbol?
A
N/m
k
11
Q
What is extention measured in?
What is it’s symbol?
A
Meters
e
12
Q
What is gravitational potential energy measured in?
What is it’s symbol?
A
J joules
Ep (small p)
13
Q
What is mass measured in?
What is its symbol?
A
kg
m
14
Q
What is the gravitational field strength measured in?
What is it’s symbol?
A
N/Kg
g
15
Q
What is hight measured in?
What is its symbol?
A
meters
h
16
Q
What is change in thermal energy measured in?
What is it’s symbol?
A
J joules
ΔE
17
Q
What is specific heat capacity measured in?
What is its symbol?
A
J/KgºC
c
18
Q
What is specific heat capacity?
A
Specific heat capacity is the amount of energy needed to rais the temprature of a 1kg substance by one ºC
19
Q
What is power?
A
The rate of energy transfer or the rate of work done
20
Q
What is time measured in?
A
Seconds
Not minutes unless you then divide the final answer by 60
21
Q
What is work done measured in?
What is its symbol?
A
J joules
W
22
Q
What is the exchange rate of juels and power?
A
1 J/s = 1 watt
23
Q
Give an example of power?
A
One moter could have more power than a different moter. The more powerful moter would lift the same weighted object the same hight as the other moter but faster. This would be because it has a higher power meaning that it is transfering energy quicker than the other moter
24
Q
What is density measured in?
What is its symbol?
A
kg/m^3
P
25
What is volume measured in?
| What is its symbol?
m^3
V
26
What does the conservation of mass state?
Mass is never created or destroyed even through evaportation or sublimate or melting ...
27
Are changes of states phycical changes or chemical?
Physical because it keeps it's original propoties of the change is reverced
28
How will changing temprature effect preasure of the gas is held at a constant volume?
Why?
Preasure will increase because the molecules are traveling faster woth more kinetic energy and force
29
What do molecules of gas and liquids do?
Hey move around in constant random motion
30
What does temprature of the gas do?
Increases kinetic energy and therefore the force exerted on a container meaning that of nothing else has changed the preasure will increase
31
What is the radius of an atom?
1x10^-10 (from the spec)
32
What is the basic structure of the atom?
It has a positivly charged nucleus made of both protons and nuetrons which are surrounded by negativly charged electrons
33
Where is most of the mass in an atom concentrated?
The nucleus
34
What is the radius of the nucleus?
1x10^-14
35
What are the shells actual name for phycics?
You need to use this
Energy levels
36
When may a electron move closer to the nucleus?
If it emitts electromagnetic radiation
37
When may a electron move further away from the nucleus?
By absorption of electromagnetic radiation
38
Why do atoms have no overal charge?
Theu have the same amount of protons as electrons
39
What is the atomic number?
Will this ever change in an isotope?
The amount of protons
No because the amount of protons is what diffines an element
40
What is the mass number?
Protons + neutron
41
What is an isotope?
An element with the same amount of protons but a different amount of neutrons
42
When do atoms become positivly charged? (+1)
If they loose an electron from their outer layer
43
How does the modle of the atom change?
By doing experiments and finding things out
The modle may change in the future
44
What did John Dalton do?
Atoms were forst described as solid spheres but made of differnet stuff
(Discovery of electron)
45
What did JJ Thomson do?
Plum Pudding model. The atom is a ball of charge with electrons embedded in it
46
What did Ernest Rutherfod discover?
The most mass is at the center of the atom. Most of it is empty space because the atoms passed straight through
The nucleus has a positive charge. Some of the positivly charged alpha particles were deflected straight back to sender
Most of the mass is at the center. Most particles only got deflected a bit but some got deflected back to sender
47
How did Ernest Rutherfod discover what he did?
The alpha scattering experiment
He fired a beam of positive aplha particles through a thin gold foil
Many went straight through but some were deflected a bit and a few were deflected straight back
This hsowed that most of the mass is in the middle (a positive nucleus) (as positives charges repel)
48
What did Nieles Bohr discover?
The electrons orbit the atom in different energy levels
49
What did James Chadwick discover?
About 20 years after the nucleus was accepted as true
There are neutrons in the nucleus. This explained the differences between the Atomic mass and the Mass number
50
What is the radius of the atom?
1X10^-10 Meters
51
What is the radius of a nucleus?
1X10^-15 Meters
52
What determines how close/far the electrons are from the nucleus?
By absorbing EM radiation they move to a higher energy level
By emmitting energy they move closer to the Nucleus
Nunim
53
What is the atomic number?
The amount of protons
54
What is the atomic mass?
The amount of protons + neutrons
55
What did Democtrius believe?
An atom was the smallest amiunt of matter you could have. It is a solid sphere that can't be divided into anything smaller
56
What are the similarities and differences between Thomson's and Rutherfords's models
JJ Thompson
No nucleus
Electorns were imbedded in the atom
Rutherfod
A densly charged positive nucleus
Both
They are spherical shaped
They contain sub atomic particles
They have a nuetral charge
57
What is radioactive decay?
| How often does it happen?
The prosses of which an unstabel nuclei gives put radiation to become more stable
THIS IS A RANDOM PROSSES
58
What is activity?
What is it measured in?
The rate of which a nuclei decays
(Bq) bacquerel
59
What is the count rate?
What is it measured in?
How is it measured?
The number of radioactive decayes recorded each second measured by a GM tube
60
What is a GM tube?
Geiger-Muller tube
Measures count rate
61
What is alpha radiation?
Consists of 2 neutrons and 2 protons (eg a helium nucleus)
62
What is beta radiation?
A high speed electron is ejected from the nucleus as a neutron terns into a proton
63
What is gamma radiation?
Electromagnetic radiation from the nucleus
64
What is neutron radiation?
?
65
Which type of radiation has the highest ionising power?
Why?
Alpha as it has the highest charge
66
Which type of radiation has the highest lowest power?
?
67
Which type of radiation has the lowest ionising power?
Why?
Gamma as they have no mass therefore if they hit something they do little damage
68
What will stop alpha rays?
A piece of paper
69
What will stop beta rays?
Alluminium foil
70
What will stop gamma rays?
Thick lead or meters of concreate
71
How far with alpha rays travel in air?
A few cm
72
How far will beta rays travel in air
A few meters
73
How far will gamma rays travel through air?
A long way
74
What is the alpha decay equasion?
a a-4 4
X = Y + He
b b-2 2
75
What is the beta decay equasion?
a a 0
X = Y + e
b b+1 -1
76
What are nuclear equasions used for?
To predict nuclear decay
77
What may happen to the element through nuclear decay?
Why?
A change in the element
It is loosing/ganing protons
78
Radon through alpha decay?
219 215 4
Radon = Polonium + He
86 84 2
79
Carbon going through beta decay?
14 14 0
Carbon = Nitrogen + e
6 7 -1
80
What happens to an element when it goes through alpha decay?
The atomic mass (top number) decreases by 4
The atomic number (bottom number) decreases by 2
81
What happens to an atom whilst it is going through beta radiation?
The atomic number (bottom number) increases by 1
82
What happens to an atom going through gamma radiation?
Nothing
83
At what rate does radioactive decay happen?
It is random
84
What is a half life?
The time it takes for the nuclei of a radioactive isotope in a sample to half
Or the amount of tome it takes the count rate (activity) to fall to half it's initial level
85
What can the particle model be used to explain?
The different states fo matter
| The difference in density
86
If a diagram has atoms more spread out it it more dense of less dense?
Less dense
87
When is something more dense?
When oarticles are packed together?
88
What are the 8 stores of energy?
Thermal
Kinetic
Gravitational potential
Elastic potential
Chemical
Magnetic
Electrostatic
Nuclear
89
How may energy be transfered?
Mechanicly (by work being done)
Electrically (movement of charges)
Heating
Radiation (eg light or sound)
90
What do we know has happened is a system changes?
Energy has been transfered
91
What is a system?
(A group of objects) Or (an object) which you (the scientist) is interested in.
92
How may energy be transfered?
Into or away a system
Between different object in a system
Beyween different energy stores
(CPG guid)
93
What is a closed system?
A system where neither matter or energy can leave
The net change in total emergy is always 0
94
How does boiling a kettle work?
The kettel's heating element transfers thermal energy into the water.
However firstly energy is transfered into the kettel's heating element through electrical energy
95
What is work done the same as?
Energy transfered
96
What are the 2 ways work can be done?
Through the movement of a current (resistance)
Or by a force moving an object
97
What haooens as a ball is thrown up into the air?
The interial force exerted by the person does work. This causes an energy transfer of chemcial (from the arm) to kinetic (movement of the ball).
After it reaches it's apex it starts to fall. It accelerated due to gravity. (The gravitational force does work). It causes wnergy to be transfered from the gravitational potential energy into kinetic energy
98
When is work done?
When something is happening
99
When do we knwo an object contains kinetic energy?
When it is moving
100
What happens in term of energy transfers when somethign speeds up?
It's kinetic energy store is increasing
101
Hwo does mass effect kinetic energy?
If it has more mass then it will need more kinetic energy to go faster
102
In calcuating kinetic energy and GPE what is mass measured in?
Kg
103
When will an object have gravitational energy?
How do we know this?
When an item is being lifted.
| The work done means that there has been a transfer of energy into the gravitational potential energy source
104
What haooens to an object as it is being lifted up?
In term of energy?
It's GPE is increasing
105
What is happening as something falls?
It's GPE energy is being transfered into kinetic energy
106
What is true of an object falling?
When?
Energy lost from the g.p.e store = energy gained in the kinetic energy store
But only in a closed system
In the reall world there will be air resistance ect
107
When is energy transfered into the elastic potential energy store?
Whenit is being streched or squashed. As long as it's limit of proportionality hasn't been exceded
108
Hen can the equasion for elastic potential energy not be used?
If the item has exceded it's limit of proportionality
109
What is specific heat capacity?
The amount of energy it takes to ehat a 1kg block of a substance by 1 degreees Celcius
110
What are charatristics of substances with a high specific heat capacity?
Theu emmit energy quickly (cool down quickly)
They can store a lot of energy
They have strong bonds
111
Hwo do you find the specific heat capacity of an object from a graph?
1 ÷ the gradient
112
What does moving a charge do?
It is a way of transfering energy because the charge does work against the resistance of the circut
113
What are electical appliences designed to do?
Transfer energy to the component in the circut when a current flows
114
Where does energy get transfered to in a kettle?
In terms of energy?
Thermal eenrgy store
115
Where does energy get transfered to in a fan?
From the electrically store (from the battery)
To the kinetic store (of the fan's motor)
116
What does an increase in current do in terms of usefull energy?
It decreases the % of useful energy as mroe energy is lost to the thermal store (and then the surroundings)
117
What is power measured in?
Watts
118
What does the total energy transfer depend on?
The power
Time used for
119
What is power?
Energy transfered per secondk
120
What are appliences labeled with?
Their power rating. This is the maximum safe power that they can opperate at
Therefore this is the most energy they can transfer each second
121
What is normally a feature of a cheaper applience?
It has a lower power rating
122
What may be a catch of an applience with a high power rating?
Although it transferes a lot of energy - not all of it may be usefull.
There may be a more energy efficent applience but with a lower power rating that would be better
123
What is potential difference?
| Electricity
Energy transered per charge passed
124
What is one way energy is transfered in a circut?
When there is a change in potential difference
125
In a circut where is energy supplied?
At the power source
eg a battery
126
What is charge flow measure in?
Coulmbos
C
127
What is voltage measured in?
Voltage
| V
128
What is potential difference equal to?
Voltage
129
What is voltage equal to?
Potential difference
130
What is current measured in?
A
Amps
131
What is resistance measured in?
Ohms
Greek letter for omega (Ω)
132
What si the symbol for current?
I
