🍏Physics Paper 1 Flashcards
Paper 1 and paper 2
1
Q
Phys: what does a step up transformer do
A
It increases pd and reduces current
2
Q
Phys: what does a step down transformer do
A
It decrease pd and increases current
3
Q
Phys: what is velocity
A
It is a vector quantity that measures speed and distance.
4
Q
Phys: what is a scalar quantity
A
It is a quantity measured solely by one value
5
Q
Phys: what is the equation for work done
A
W = F x D
6
Q
Phys: what is the equation for spring constant
A
Force / extension
7
Q
Phys: what is the equation for elastic potential energy
A
0.5 x k x e^2 (half x spring constant x extension squared)
8
Q
Phys: what happens to resistance in parallel
A
It is smaller than the smallest resistor
9
Q
Phys: what happens to current in parallel
A
Current splits among the loops based upon the resistances of the components
If one loop has a resistance of 6 ohms and one a resistance of 3 and the total current is 3A, the first loop has 2A and the second 1A
10
Q
Phys: what happens to p.d. in parallel
A
P.d. Is constant among the loops
11
Q
Phys: what happens to current in series
A
Current is constant
12
Q
Phys: what happens to p.d. In series
A
P.d. Is shared among the components
13
Q
Phys: what happens to resistance in series
A
It is a sum if the resistors
14
Q
Phys: what is electrical work done
A
It is the work done when current flows, its equation is E = VIT
15
Q
Phys: how many electrons in one coloumb
A
6.24 x 10^18 electrons
16
Q
Phys: what is current
A
The rate of flow of charge
17
Q
Phys: what is potential difference
A
It is a measure of work done / energy transferred, per coloumb of charge
18
Q
Phys: which direction does conventional current flow
A
Anti clockwise
19
Q
Phys: how is resistance caused in a wire
A
The electrons collide with he side of the wire or on the metal ions in the wire because the electrons do not take a straight path
20
Q
Phys: what is ohms law and name one ohmic conductor
A
Current is directly proportional to resistance, a reisstor follows ohms law
21
Q
Phys: what is direct potential differnece
A
P.d. With a constant polarity
22
Q
Phys: what is alternating p.d.
A
P.d. Polarity keeps switching
23
Q
Phys: what is mains electricity in hz and p.d.
A
50Hz alternating p.d. And 230v
24
Q
Phys: what is chemical energy stored in
A
The bonds in the atoms
25
Phys: what is activity
The amount of deacys per second
26
Phys: what is a bequerel
Bq it is the unit of activity
27
Phys: what is a half life
The avarage time taken for half of the radioactive nuclei to decay
28
Phys: what is the equation for latent heat
Energy/mass
29
Phys: what is latent heat
The energy required to change a substances state without changing its temeprature
30
Phys: what is specific heat capacity
The energy required to change the temp of 1 kg of a substance by 1 degree C
31
Phys: what is nuclear fusion
Is is where small nuclei form larger particles
32
Phys: during fusion what elements are used and what is produced
Deuterium, tritium, helium is produced and one neutron
33
Phys: what is binding energy
The energy required to remove a particle from a system
34
Phys: what is sublimation
When a substance changes state from solid to gas without becoming a liquid
35
Phys: what is the specific heat capacity of water
4200 j/kg°C
36
Phys: what materials are affected by magnets
Magnetic (cobalt nickel iron) or moving charged objects, check
37
Phys: what is conventional current
Current flowing from pos to neg
38
Phys: define half life in 3 ways
- time for activity to half
- time for count rate to half
- time for number of radioactive isotopes to decay
39
Phys: how do you calculate rate on a curve
Draw a tangent and do change in y over change in x
40
Phys: what is activity (equation)
Number of decays / time, measured in Bq
41
Phys: explain how you get an electric shock from a live wire
- You complete the circuit by grounding it
- there is a potential difference between you and the wire
- current flows through you
42
Phys: define electric fields, what direction does it go
The region around a charged particle where another charged particle will feel a force, it goes from positive to negative, or in a positive charge outward
43
Phys: define velocity
The speed in a certain direction
44
Phys: define induced magnet
It is an object that is a magnet when it is in a magnetic field
45
Phys: what is a GJ
Billion joules
46
Phys: describe the process of nuclear fission
- uranium NUCLEUS
- absorbs a neutron
- becomes unstable and splits, forming 2 smaller daughter nuclei of similar size
- releases 2 or 3 neutrons gamma rays and some mass converted to energy
47
Phys: what is the equation for charge
Q = I x t
48
Phys: what is the equation for electrical energy
E = Q x V
49
Phys: what happens to an LDR when light intensity increases
Resistance decreases
Current increases
50
Phys: what happens to a thermistor when heat increases
Resistance decreases
Current increases
51
Phys: what is faster to cool down, high or low specific heat capacity
Low
52
Phys what is slower to cool down, high or low specific heat capacity
High
53
Phys: what happens in beta decay
One neutron splits into a proton and an electron, this increases the charge of the nucleus, the proton number goes up
54
Phys: if you touch a van de Graf generator what charge do you gain
The same charge as the generator
55
Phys: what is the average range for human reaction speed
0.2 to 0.9
56
Phys: what is the equation for stopping distance
Stopping distance = thinking distance + braking distance
57
Phys: What affect does mass have on breaking distance
Greater mass = greater Ke, means it takes **longer** to stop with the same friction and speed
58
Phys: what equation links resistance, power and current
P = I^2R
59
Phys: what equation links power, current and voltage
P = IV
60
Phys: what equation links voltage current and resistance
V = IR
61
Phys: what is the equation for Ke
Ke = 1/2 x mass x velocity^2
62
Phys: what is the equation for elastic potential energy
Epe = 1/2 x constant x extension^2
63
Phys: what is the equation for GPE
GPE = M x H x G ( Mass X Hight X Gravity )
64
Phys: what is the equation that links charge, time and current
Charge = current x time
Q = It
65
phys: who came up with the plum pudding model, when?
JJ thompson, 1897
66
phys: who thought the atom was a nucleus with all of the posotive charge in the center and a cloud of neagtive charge, when
Ernest Rutherford, 1909
67
phys: who came up with the idea that electrons were in shells with orbits, and when?
Niels Bohr, 1913
68
phys: who came up with the idea of protons, when?
Rutherford, 1919
69
phys: who came up with the idea of neutrons and when
James Chadwick, 1932
70
phys: what are the 4 properties of solids
- the most dence of the states of matter
- in a regular arrangement
- particles vibrate around a fixed position
- they have strong intermolecular forces of attraction
71
phys: what are the 4 properties of liquids
- they are less dence than a solid
- they are in an irregular arrangement
- particles can flow over and around eachother
- they have weaker intermolecular forces of attraction than solids
72
phys: what are the 4 properties of gases
- they have an irregular arrangement
- they are in constant random motion
- **no** intermolecular forces of attraction
- it has the lowest dencity of the states of matter and there are large gaps between the atoms
73
Phys: what is the equation for latent heat
Energy/mass
74
Phys: what are the 2 parts of the internal store
- total Ke of the particles due to their movement (temp)
- potential energy due to their position (state)
75
Phys: what is the device used to measure the volume of a irregular shaped object
eureka can
76
Phys: what is a rheostat
It is a type of variable resistor
77
phys: is force vector or scalar
vector
78
Phys: How to calculate half life
Half life = 0.693/decay constant
79
Phys: in mains electricity what colour is the live wire
Brown
80
Phys: in mains electricity what colour is the neutral wire
Blue
81
Phys: in mains electricity what colour is the earth wire
Green and yellow
82
Phys: what wire is connected to the fuse in plug
Live
83
Phys: what is 2.55 +/- 0.1 g/cm^3
Lower bound: 2.45
Upper bound: 2.65
84
Phys: why is a mean more accurate
Becuse it reduces the affect or random errors
85
Phys: what does the inside of a plug look like
86
Phys: define a closed system
A system that experiences no net change in its total energy when energy transfers occur within it
87
Phys: what happens when a student touches a positively charged van de Graf generator
The gain the same charge as it because **electrons are transferred**
88
Phys: what material will beta radiation not penetrate
Aluminium **sheet**
89
Phys: how far can alpha radiation travel in air
~3cm
90
Phys: why does pressure increase in a syringe when it s plunger is pushed
- air particles are closer together
- freq of collisions between particles and syringe will increase
- large force for smaller area means higher pressure.
91
Phys: define efficiency
The proportion of energy transferred usefully
92
Phys: what is speed
Is is a scalar magnitude that measures speed without a direction
93
Phys: what did Bohr add to the atomic model
Energy levels
94
Phys: what is irradiation
Exposure to emissions of radioactive decay
95
Phys: what is contamination
It is making something radioactive
96
Phys: what happens when more resistors are added in parallel
- as more resistors are added total resistance decreases
- current goes up and power drawn goes up
- resistance total is less than smallest resistor
97
Phys: what is the symbol equation for speed = distance / time
V = d/t
98
Phys: what is a system
It is a group of objects
99
Phys: what happens when a system changes
There are changes in the way energy is stored
100
Phys: what are 2 ways of reducing unwanted energy transfers
- thermal insulation
- lubrication
101
Phys: what is higher when the thermal conductivity of a material is higher
The rate of energy transfer is higher
102
Phys: how is the rate of cooling of a building affected by teh thickness of its walls
add
103
Phys: what are the main energy resources available for use on earth
- fossil fuels
- nuclear fuel
- bio-fuel
- wind
- hydro-electrisity
- geothermal
- tides
- sun
- water waves
104
Phys: what is the circuit symbol for a switch (open)
105
Phys: what is the circuit symbol for a lamp
106
Phys: what is the circuit symbol for a cell
107
Phys: what is the circuit symbol for a switch (closed)
108
Phys: what is the circuit symbol for a voltmeter
109
Phys: what is the circuit symbol for a battery
110
Phys: what is the circuit symbol for an ammeter
111
Phys: what is the circuit symbol for a diode
112
Phys: what is the circuit symbol for a thermistor
113
Phys: what is the circuit symbol for a variable resistor
114
Phys: what is the circuit symbol for an LDR
115
Phys: what is the circuit symbol for an LED
116
Phys: what is an LED
Light emitting diode
117
Phys: what is an LDR
Light Dependent Resistor
118
Phys: what is required for current to flow though a closed circuit
The circuit must include a source of potential difference
119
Phys: in a single closed loop what is a property of current
current has the same value, check
120
Phys: what happens in a filament lamp as temperature increases
Resistacne increases
121
Phys: what does the graph of p.d. to current for a filament lamp look like
122
Phys: what does the graph of p.d. to current for a diode
123
Phys: in the reverse direction of a diode what happens
There is a very high resistance
124
Phys: what are the applications of thermistors
Thermostats
125
Phys: what are the properties of strength for an electric field
closer to the electric field the force is stronger
126
Phys: what is the national grid
It is a system of cables and transformers linking power stations to consumers
127
Phys: what happens when a charge flows in a circuit
Work is done
128
Phys: what does the amount of energy an appliance transfers depend on
- how long the appliance is switched on for
- the power of the appliance
129
Phys: what does the live wire carry in a plug socket
**alternating** potential difference from the supply
130
Phys: what does the neutral wire do in a plug socket
It completes the circuit
131
Phys: what does the earth wire do in plug sockets
It is a safety wire to stop the appliance becoming live
132
Phys: what is the potential difference between the live wire and earth (0v) in a plug socket
About 230 v
133
Phys: what is the voltage of the earth wire in a plug socket
0v
134
Phys: what is the voltage of the earth wire in a plug socket
0v, it only carries a current if there is a fault
135
Phys: what type of transformers are used by power stations to the grid
Step up transformers, they increase P.d. and decrease current
136
Phys: from grid to home what transformer is used
Step down transformer, decrease p.d increase current for use
137
Phys: what type of change are changes of state
They are physical changes because the material recovers its original properties if the change in reversed
138
Phys: in a system what stores the energy and what is that called
The particles, it is called internal energy
139
Phys: in nuclear fusion what is the type of energy that matter could be turned into
Radiation
140
Phys: what type of nuclear fission is rare
Spontaneous fission
141
Phys: what type of reaction is in a nuclear weapon
An uncontrolled fission and/or fusion
142
Phys: in medicines what is radiation used for
- exploration of internal organs
- control or destruction of unwanted tissues
143
Phys: what is background radiation (dose) affected by
- occupation
- location
144
Phys: what causes background radiation
- natural sources such as rocks, cosmic rays from space
- man made sources such as the fallout from nuclear weapons testing and nuclear accidents
145
Phys: what are the prerequisites for the pressure X volume = constant
A fixed mass of gas held at a constant temperature
146
Phys: when a gas is compressed or expanded by pressure changes what type of net force is produced
One at right angles to the wall of the gas container
147
Phys: if a gas is held at a constant volume and temperature changes what happens to pressure
It changes
148
Phys: what is a property of the particles in gas
They are in constant random motion
149
Phys: what is the specific latent heat of a substance
It is the amount of energy required to change the state of one kilogram of the substance with no change in temperature
150
Phys: what is the energy needed for a substance to change its state
Latent heat
151
Phys: why does temperature not change during a state change
Energy is converted into internal energy not temperature
152
Phys: if the temp of a system increases what does this increase depend on
The mass of the substance heated and the type of material heated and the energy input of the system
153
Phys: why is it important that the findings of studies into the affect of radiation on humans be published
So that it can be peer reviewed check (just before 4.4.3)
154
Phys: what is the **random** process of radioactive decay
It is where unstable nuclei give out radiation as it changes to become more stable
155
Phys: what is count rate
It is the number of decays recorded each second by a detector (e.g. geiger-muller tube)
156
Phys: what does gamma emissions not do to the atom
It does not change mass or charge (for GCSE)
157
Phys: what is work
It is the transfer of energy by a force
158
Phys: what does doing work on gas do
It increases the internal energy of the gas and can cause an increase in the temp of the gas
159
Phys: before the discovery of the electron what was thought about an atom
That they were tiny spheres that could not be divided
160
Phys: what model of the atom did the discovery of the electron lead to
The plum pudding model
161
Phys: what did the results of the alpha particle scattering experiment lead to
The conclusion that the mass of an atom was concentrated in the center and that it was charged, the nuclear model replaced the plum pudding model
162
Phys: what is a beta particle
It is a high speed electron ejected from the nucleus as a neutron splits into a proton
163
Phys: what is an alpha particle
It consists of 2 neutron and 2 protons (same as a helium nucleus)
164
Phys: what is a gamma particle
Electromagnetic radiation from the nucleus a neutron
165
Phys: how were neutrons discovered
Experiments led to the idea that the positive charge of any nucleus could be subdivided into a whole number of smaller particles, each having the same amount of positive charge
166
Phys: if an atom loses an outer shell electron what happens to it
It becomes a positive ion
167
Phys: what is the radius of an atom roughly
1 x 10 ^ -10 meters
168
Phys: what is the radius of the nucleus of an atom in comparison to the atom
1/10,000, most of the mass of an atom is in the nucleus
169
Phys: what is it called when electrons are at different distances from the nucleus
Energy levels
170
Phys: how can electron arrangements change
An electron from a lower energy level can absorb electromagnetic radiation and go 'up an energy level', or by the emission of electromagnetic radiation where an electron moves down an energy level
171
Phys: what is the purpose of thermal insulation
To reduce thermal energy transfer
172
Phys: how does an electromagnet work
- when current flows
- the coil gains a magnetic field
- the iron core gets magnetised
173
Phys: how do you make a transformer
You wrap **insulated** wire on one side of an iron (or magnetic) core and more on the other side in a diff loop/circuit
174
Phys: if the secondary coil of a transformer has more turns what is the transformer
Step up
175
Phys: if the secondary coil of a transformer has more less what is the transformer
Step down
