Spec point which is NOT in Triple Science
3.05 know and use the relationship between the speed, frequency and wavelength of a wave: v = f × λ
wave speed (m/s) = frequency (Hz) x Wavelength (m)
3.06 use the relationship between frequency and time period: time period x frequency = 1 or f = 1/T
Frequency (Hz) = 1/ Time Period (s)
3.07 use the above relationships in different contexts including sound waves and electromagnetic waves
You will need to use any of the in 3.05 and 3.06 to solve problems to do with sound waves and electromagnetic (light) waves
3.10 know that light is part of a continuous electromagnetic spectrum that includes radio, microwave, infrared, visible, ultraviolet, x-ray and gamma ray radiations and that all these waves travel at the same speed in free space
Electromagnetic Spectrum:
- A continuous spectrum of waves of differing frequency.
- All electromagnetic waves have the following properties:
- Transfer energy
- Are transverse waves
- Travel at the speed of light in a vacuum
- Can be reflected and refracted
3.11 know the order of the electromagnetic spectrum in terms of decreasing wavelength and increasing frequency, including the colours of the visible spectrum
Radio Waves
Microwaves
Infrared (IR)
Visible Light
Ultraviolet (UV)
X – Rays
Gamma Rays
these are written in order of increasing frequency, lowest at the top
and decreasing wavelength, lowest at the bottom.
the colours displayed are in order of lowest frequency to the left highest frequency to the right.
3.12 Explain some of the uses of electromagnetic radiations, including: radio waves: broadcasting and communications, microwaves: cooking and satellite transmissions, infrared: heaters and night vision equipment, visible light: optical fibres and photography, ultraviolet: fluorescent lamps, x-rays: observing the internal structure of objects and materials, including for medical applications, gamma rays: sterilising food and medical equipment.
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uses of electromagnetic radiations, including: |
3.13 explain the detrimental effects of excessive exposure of the human body to electromagnetic waves, including: microwaves: internal heating of body tissue, infrared: skin burns, ultraviolet: damage to surface cells and blindness, gamma rays: cancer, mutation and describe simple protective measures against the risks
the detrimental effects of excessive exposure of the human body to electromagnetic waves:
• microwaves: internal heating of body tissue
• infrared: skin burns
• ultraviolet: damage to surface cells and blindness
• gamma rays: cancer, mutation
to reduce the risks:
- wear sun glasses, sun cream and stay in shade for UV
- Wear led clothing for Gamma
3.14 know that light waves are transverse waves and that they can be reflected and refracted
light is a transverse wave that can be reflected and refracted
3.17 practical: investigate the refraction of light, using rectangular blocks, semi-circular blocks and triangular prisms
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1. Set up your apparatus as shown in the diagram using a rectangular block. 2. Shine the light ray through the glass block 3. Use crosses to mark the path of the ray. 4. Join up crosses with a ruler 5. Draw on a normal where the ray enters the glass block 6. Measure the angle of incidence and the angle of refraction and add these to your results table 7. Comment on how the speed of the light has changed as the light moves between the mediums. 8. Repeat this for different angles of incidence and different glass prisms. |
3.19 practical: investigate the refractive index of glass, using a glass block
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1. Set up your apparatus as shown in the diagram using a rectangular block. 2. Shine the light ray through the glass block 3. Use crosses to mark the path of the ray. 4. Join up crosses with a ruler 5. Draw on a normal where the ray enters the glass block 6. Measure the angle of incidence and the angle of refraction and add these to your results table 7. Calculate the refractive 8. Repeat steps 2 – 7 using 9. Find an average of your
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3.20 describe the role of total internal reflection in transmitting information along optical fibres and in prisms
Total Internal Reflection:
- Used to transmit signals along optical fibres.
3.21 explain the meaning of critical angle c
Critical Angle:
- The angle of incidence which produces an angle of refraction of 900 (refracted ray is along the boundary of the surface).
- When the angle of incidence is greater than the critical angle, total internal reflection occurs (all light is reflected at the boundary).
- This effect only occurs at a boundary from a high refractive index material to a low refractive index material.
3.22 know and use the relationship between critical angle and refractive index:
also remember:
critical angle = sin-1(1/n)
3.23 know that sound waves are longitudinal waves which can be reflected and refracted
sound waves are longitudinal waves which can be reflected and refracted.
4.01 use the following units: kilogram (kg), joule (J), metre (m), metre/second (m/s), metre/second2 (m/s2), newton (N), second (s) and watt (W)
know the units for
Mass = kilogram (kg)
energy = joule (J)
velocity = metre/second (m/s)
acelleration = metre/ second 2 (m/s2)
force = newton (N)
time = second (s)
power = watt (W)
4.02 describe energy transfers involving energy stores: energy stores: chemical, kinetic, gravitational, elastic, thermal, magnetic, electrostatic, nuclear and energy transfers: mechanically, electrically, by heating, by radiation (light and sound)
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Energy Stores: Chemical – e.g. the food we eat Kinetic – movement energy Gravitational – objects that are lifted up Elastic – e.g. from springs Thermal – from hot objects Magnetic – objects in magnetic fields Electrostatic – charged objects Nuclear – stored within a nucleus
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4.03 use the principle of conservation of energy
In any process energy is never created or destroyed. (It is just transferred from one store to another.)
4.05 describe a variety of everyday and scientific devices and situations, explaining the transfer of the input energy in terms of the above relationship, including their representation by Sankey diagrams
The energy flow is shown by arrows whose width is proportional to the amount of energy involved. The wasted and useful energy outputs are shown by different arrows.
4.11 know and use the relationship between work done, force and distance moved in the direction of the force: W = F × d
Work Done (J) = Force (N) x distance moved (m)
4.12 know that work done is equal to energy transferred
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Work done = energy transferred |
4.13 know and use the relationship between gravitational potential energy, mass, gravitational field strength and height: GPE = m × g × h
Gravitational potential energy (J) = Mass (kg) x gravitational field strength (N/kg) x height (m)
4.14 know and use the relationship: kinetic energy = 1/2×m×v^2
Kinetic energy (J) = 0.5 x mass (kg) x velocity (m/s) 2
4.15 understand how conservation of energy produces a link between gravitational potential energy, kinetic energy and work
Because energy is conserved the decrease in GPE = increase in KE, for a falling object if no energy is lost to the surroundings
4.16 describe power as the rate of transfer of energy or the rate of doing work
power is the rate of transfer of energy, or the rate of work done. so p = E/t
5.01 use the following units: degree Celsius (°C), Kelvin (K), joule (J), kilogram (kg), kilogram/metre3 (kg/m3), metre (m), metre2 (m2), metre3 (m3), metre/second (m/s), metre/second2 (m/s2), newton (N) and pascal (Pa)
The units for:
temperature: degree Celsius (°C) or Kelvin (K)
Energy: Joule (J)
mass: Kilogram (kg)
density: kilogram/metre cubed (kg/m3)
distance: metre (m)
area: metre squared (m2)
volume: metre cubed (m3)
velocity: metre per second (m/s)
acceleration: metre per second squared (m/s2)
force: newton (N)
pressure: pascal (Pa)
5.02 use the following unit: joules/kilogram degree Celsius (J/kg °C)
the unit for
specific heat capacity: joules/kilogram degree Celsius (J/kg °C)
5.03 know and use the relationship between density, mass and volume:
Units of density depend on units used for mass and volume:
E.g. mass in [g] and volume in [cm3] gives density in [g/cm3], however mass in [kg] and volume in [m3] gives density in [kg/m3].
5.04 practical: investigate density using direct measurements of mass and volume
- The density of an object can be found by measuring the mass and volume and applying the formula above to calculate the density.
- For a regular object use a ruler to measure the lengths needed to determine the volume.
- For an irregular object submerge it in water and measure the displaced volume.
- Measure the mass of either type of object using a measuring balance.
5.05 know and use the relationship between pressure, force and area:
pressure (Pa) = force (N)/ area (m2)
- Pressure is defined as force per unit area.
- One pascal (Pa) is equivalent to one N/m2
5.07 know and use the relationship for pressure difference: p = h × ρ × g
Pressure difference [Pa] = Density [kg/m3] x g [N/kg] x Height [m]
ΔP = ρ g h
- The equation can be used in liquids or gases provided you know their densities.
P1 – Patm = ρ g h
P1 = ρ g h + Patm
5.15 explain how molecules in a gas have random motion and that they exert a force and hence a pressure on the walls of a container
Gas laws:
- Gas molecules have rapid and random motion.
- When they hit the walls of the container, they exert a force.
- Pressure = Force/Area
5.16 understand why there is an absolute zero of temperature which is –273 °C
Absolute zero:
- At absolute zero the particles have no thermal energy or kinetic energy, so they cannot exert a force.
- Absolute zero = 0 Kelvin = -2730C
5.17 describe the Kelvin scale of temperature and be able to convert between the Kelvin and Celsius scales
0 K = -273 0C
E.g. 100K = -1730C
2000C = 473K
5.18 understand why an increase in temperature results in an increase in the average speed of gas molecules
As you increase the temperature of a gas, the kinetic energy of the gas particles increases and thus their average speed also increases.
5.19 know that the Kelvin temperature of a gas is proportional to the average kinetic energy of its molecules
The Kelvin temperature of a gas is proportional to the average kinetic energy of its molecules.
5.20 Explain, for a fixed amount of gas, the qualitative relationship between: pressure and volume at constant temperature, pressure and Kelvin temperature at constant volume.
- As you heat the gas, the kinetic energy of the particles increases, and thus so does their average speed.
- This means more collisions per second with the walls, and they exert a larger force on the wall.
- This causes in the total pressure being exerted by the particles to rise.
- If temperature is constant, the average speed of the particles is constant.
- If the same number of particles is placed in a container of smaller volume they will hit the walls of the container more often.
- More collisions per second means that the particles are exerting a larger force on the wall over the same time, so average force exerted on the walls has increased.
5.21 use the relationship between the pressure and Kelvin temperature of a fixed mass of gas at constant volume:
P1/T1 = P2/T2
*Temperature must be in Kelvin
Temperature law:
For a fixed mass of gas at constant volume, the pressure is directly proportional to the Kelvin temperature
5.22 use the relationship between the pressure and volume of a fixed mass of gas at constant temperature:
P1V1 = P2V2
Boyle’s law:
For a fixed mass of gas at constant temperature, the pressure is inversely proportional to the volume.
6.01 use the following units: ampere (A), volt (V) and watt (W)
The unit for:
Current : amps (A)
Potential Difference : volt (V)
power : watt (W)
6.02 know that magnets repel and attract other magnets and attract magnetic substances
Opposites attract: North attracts South and South attracts North
Like charges repel: Two Norths will repel each other
6.03 describe the properties of magnetically hard and soft materials
Permanent magnets are made of magnetically hard materials such as steel. These materials retain their magnetism once magnetised.
Some materials like iron are magnetically soft. They lose their magnetism once they are no longer exposed to a magnetic field. They are used as temporary magnets such as electromagnets.
6.04 understand the term magnetic field line
Around every magnet there is a region of space where we can detect magnetism (where magnetic materials will be affected).
This is called the magnetic field and in a diagram we represent this with magnetic field lines.
The magnetic field lines should always point from north to south.
6.05 know that magnetism is induced in some materials when they are placed in a magnetic field
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When magnetic materials are bought near or touch the pole of a strong or permanent magnet, they become magnets. This magnetic character is induced in the objects and it is removed when the permanent magnet is removed. This is a temporary magnet Magnetism is induced in the paperclips so each paperclip can attract another one |
6.06 practical: investigate the magnetic field pattern for a permanent bar magnet and between two bar magnets
- Place your bar magnet in the centre of the next page and draw around it.
- Place a compass at one pole of the bar magnet.
- Draw a ‘dot’ to show there the compass is pointing,
- Move the compass so the opposite end of the needle is pointing to the dot,
- Repeat steps 3 and 4 until to reach the other pole of the magnet.
- Do this procedure at least 5 times from different points on the pole of the magnet.
*Tip, try to be as accurate as possible when drawing your dots* - Join up your dots to create the field line plots