Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physics Nat 5 > Physics Theory > Flashcards

Physics Theory Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

What are longitudinal waves?

A

When the vibrations move in the same direction as the energy travels in e.g. sound waves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are transverse waves?

A

When the vibrations move at right angles to the direction the energy travels in e.g. visible light, EM spectrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Do long wavelengths or short wavelengths diffract more?

A

Long wavelengths diffract (bend) more than short wavelengths

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Do waves diffract more through a narrow gap or wider gap?

A

Waves diffract more through a narrow gap

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

List the waves of the EM spectrum in order?

A

Gamma rays, X-rays, Ultraviolet, Visible Light, Infrared, Microwaves, Radiowaves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What do all the waves in the EM Spectrum have in common?

A

-Travel at the speed of light
-Can travel through a vacuum
-Can be reflected
-Can be refracted
-Can be diffracted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

List the colours of the visible spectrum from highest wavelength to lowest

A

red. orange, yellow, green, blue, indigo, violet
(ROYGBIV)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Define the particles in an atom

A

Proton: postive, mass=1, located in the nucleus
Electron: negative, mass= near 0, orbits the nucleus
Neutron: charge is 0, mass=1, located at the nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Define Ionisation

A

The process of adding or removing electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Define Ionising Radiation

A

Materials that can cause ionisation in other atoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Define the radiation type ‘Alpha’

A

Symbol: α
It is a Helium nucleus
Highly ionising
Absorbed by air or paper

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Define the radiation type ‘Beta’

A

Symbol: β
It is a fast electron
Less ionising than alpha more than gamma
Absorbed by mms of aluminium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define the radiation type ‘Gamma’

A

Symbol: γ
It is a high energy wave in the Em Spectrum
Not very ionising
Absorbed by a few cms of lead

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the types of natural background radiation?

A

-Radan Gas
-Cosmic rays from the sun and outer space
-Rocks and Soil
-Foods (e.g. banana)
-The Human body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the types of artificial background radiation?

A

-Medical sources, e.g. x-rays
-Fall out from weapon testing
-Nuclear Power stations
-Radioactive waste

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the Half-Life Experiment

A
  1. To ensure a fair test measure the background radiation
  2. Use a geiger muller tube to count the number of decays from a source in a minute. Take away from the background radiation count
  3. Calculate activity over the minute (A=N/t)
  4. Repeat process at regular intervals
  5. Plot activity (y-axis) against time (x-axis)
  6. Use graph to find half life
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does the risk of biological harm from exposure to radiation depend on?

A

-The Absorbed dose
-The type of radiation (alpha, beta, gamma)
-The body/organs/tissue exposed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Define Nuclear Fission

A

The splitting of a large and unstable nuclei, into 2 more stable nuclei neutrons whilst energy is released

19
Q

Define a chain reaction during Nuclear Fission

A

When the neutrons produced by the fission reaction can then go on to further reactions

20
Q

Define Nuclear Fusion

A

When 2 light nuclei combine to make a bigger nucleus, producing extra energy

21
Q

Why is Nuclear Fusion mostly impossible on Earth?

A

-Fusion is how stars produce their energy
-It is difficult (close to impossible) to do on Earth for electricity production
-This is because fusion requires high temperatures and and abundance of light elements are required

22
Q

What are the Pros of Nuclear Power?

A

-Clean: doesn’t produce CO2 and greenhouse gases
-Little fuel is required to produce a lot of energy

23
Q

What are the cons of nuclear power?

A

-Non-renewable energy source
-A serious accident in a nuclear power station is a major disaster
-Nuclear power stations produce radioactive waste, some of which is very difficult to deal with
-After a few decades nuclear power stations themselves will have to be disposed of

24
Q

What are the ways to keep safe around nuclear radiation?

A

-Use forceps to pick up source
-No contact with skin
-Protective clothing e.g. lead apron
-Limit time with source
-Point away from the body

25
Q

What is the experiment for Instantaneous speed?

A
  1. Measure the distance, d, with a ruler, metre stick or trundle wheel.
  2. Measure the time taken, t, with a stop clock.
  3. Calculate the average speed by dividing the distance travelled by the time taken.
26
Q

List examples of vectors

A

velocity
displacement
acceleration
force
momentum

27
Q

List examples of scalars

A

speed
distance
time
mass
energy

28
Q

What is Newtons First Law?

A

An object will stay at rest or keep moving in a straight line at a constant speed if balanced forces are acting on it

29
Q

What is Newtons Second Law?

A

Unbalanced Force=mass x acceleration

30
Q

What is Newtons Third Law?

A

Every action has an equal and opposite reaction

31
Q

What is a satellite

A

-They are objects that orbit a planet
-They can be natural e.g. the moon
-They can be man-made e.g. international space station
-The larger the height the longer the orbital period

32
Q

Define a Geostationary Satellite

A

-A satellite that remains above the same point of the Earths Surface
-Has an orbital period of 24hrs
-They orbit Earth 36,000km above the Earths surface and are used for telecommuncations

33
Q

What happens during Re-entry?

A

When the spacecraft enters the Earth’s atmosphere there is an energy change: Kinetic to Heat
This is due to the friction between the particles in the atmosphere and the outer surface of the space shuttle rumbling against eachother

34
Q

How can we counteract the large energy transfer during Re-entry?

A

-Silica tiles are used to protect from the heat. The tiles are painted black so that heat is lost to the surroundings
-This is commonly known as a heat shield

35
Q

What is the Big Bang Theory?

A

-Scientists estimate the age of the universe to be 13.8 billion years old
-The universe seems to be expanding from a single point
-Scientists don’t have any firm evidence that the Big Bang Theory actually happened

36
Q

What is the evidence that supports the Big Bang Theory

A

-Red shift and expanding universe
-Abundance of light elements
-Cosmic microwave background radiation

37
Q

What is the law of conservation of energy?

A

Energy cannot be created or destroyed. It can only be changed from one form to the other.

38
Q

Define Potential Difference

A

This is the energy given to each coulomb of charge passing through the supply

39
Q

Define Direct Current (DC)

A

The flow of electrons through a circuit are in one direction only.
e.g. batteries, electronic equipment, solar cells

40
Q

Define Alternating Current

A

The flow of charge (electrons) regularly reverses its direction through the circuit with time.

41
Q

What happens to a transistor when it’s dark

A

-As the light level of the LDR decreases the resistance of the LDR increases
-This means the voltage of the LDR will increase also
-When this voltage over the LDR reaches a certain value, the transistor will conduct
-Current will flow to the bulb and switch it on

42
Q

What happens to a transistor when it’s light

A

-As the light level of teh LDR increases the resistance of the LDR decreases
-This means the voltage of the LDR will decrease also
-The Voltage over the V2 will therefore increase
-When this voltage over the resistor reaches a certain value, the transistor will conduct
-Current will flow to the bulb and switch it on

43
Q

What happens to a transistor when it’s cold

A

-As the temperature of the thermisor decreases the resistance of the thermistor will increase
-This means the voltage of the thermistorwill increase also
-When this voltage over the thermisor reaches a certain value, the transistor will conduct
-Current will flow to the bulb and switch it on

44
Q

What happens to a transistor when it’s hot

A

-As the temperature of the thermistor increases the resistance of the thermistor decreases
-This means the voltage of the thermistor will decrease also
-The voltage over the resistor will therefore increase
-When the voltage over the resistor reaches a certain value, the transistor will conduct
-Current will flow to the bulb and switch it on

Physics Nat 5 (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions