physics 1 Flashcards
What is a fossil fuel?
A natural fuel such as coal, oil or natural gas, formed in the geological past from the remains of living organisms.
How is coal formed?
Plant fossils turn into coal after many years of being pressed into layers of earth.
How is oil formed?
The sun gives energy to plants floating in the ocean. Sea creatures eat the tiny plants, die and get buried under sediment. Over time soft parts turn to oil. This is then pumped out of the ocean.
How is natural gas formed?
Sun gives energy to plants floating in the ocean. Plants die and bury. The break down to form gas. The gas is piped up for energy.
How does a steam turbine generate energy?
steam is formed when water is boiled. The steam at high pressure turns a turbine. A generator is connected to the turbine which transforms kinetic energy into electrical.
Ways of generating electricity are..
Fossil fuels, solar, tidal, wind, wave, Nuclear,Hydroelectric
What are the advantages of Oil?
It can be easily stored and transported from one place to another.
What are the advantages of Coal?
It is cheaper and more affordable.
What are the advantages of Natural gas?
Natural gas is the cleanest fossil fuel and a highly efficient form of energy. It has fewer impurities, is less chemically complex, and its combustion results in less pollution.
What are the disadvantages of fossil fuels?
They are not renewable energy sources. Powering plants, factories your home or car with fossil fuels leads to the release of high levels of carbon dioxide. Fossil fuels are not green sources of energy.
How is energy transferred to our homes?
Electricity is transferred from power stations to consumers through the wires and cables of the National Grid. When a current flows through a wire some energy is lost as heat. The higher the current, the more heat is lost. To reduce these losses, the National Grid transmits electricity at a low current. This needs a high voltage.
At what voltage is electricity supplied to your home?
It is produced at 22000V in a power station but step down transformers step down the voltage to 230V for your home.
What is carbon capture?
It is when CO2 is captured from the environment, stored, and pumped underground where if pressure is high, it could solidify.
What types of fuel do nuclear power stations use to release energy and what is the reaction called?
uranium, plutonium
nuclear fission.
What is biomass?
Living or once living matter.
What is the national grid?
A network of cables running across the country.
What happens when you increase voltage?
The current goes down.
What are waves?
Oscillations or vibrations of particles which transfer energy not matter.
What happens in a sound wave?
Air particles vibrate back and forth, causing compressions and rarefractions
What is wavelength?
The shortest distance between two coherent points on the same wave. E.g. the distance from peak to peak.
What is frequency?
The number of waves passing a point each second.
What is amplitude?
The maximum height of the wave measured from the middle.
What are the 2 types of waves?
Longitudinal and transverse waves. Both are seismic waves.
What are longitudinal waves?
Sound–>Oscillation–>Compression and rarefraction of particles.
In longitudinal waves, the vibrations are along the same direction as the direction of travel. They are P waves.
What are transverse waves?
Light–>Oscillation are perpendicular to direction of energy–>Peak and troughs.
In transverse waves, the vibrations are at right angles to the direction of travel. They are S waves.
What is a trough?
The lowest point is called the trough.
What is rarefraction?
The opposite of compressions.
What is a peak
The highest point on a wave is called the peak.
What is amplitude?
The amplitude of a wave is its maximum disturbance from its undisturbed position. Take care, the amplitude is not the distance between the top and bottom of a wave.
See diagram in book.
What is the wavelength?
The wavelength of a wave is the distance between a point on one wave and the same point on the next wave, but it doesn’t matter where as long as it is the same point in each wave.
What is the wave equation?
Wave Speed = Frequency x Wavelength
V = f x λ
What is the angle of incidence?
The angle which an incident line or ray makes with a perpendicular to the surface at the point of incidence.
What is the angle of reflection?
the angle made by a reflected ray with a perpendicular to the reflecting surface.
What is refraction?
Refraction is the bending of a wave when it enters a medium where its speed is different. The refraction of light when it passes from a fast medium to a slow medium bends the light ray toward the normal to the boundary between the two media.
What is diffraction?
When waves meet a gap in a barrier, they carry on through the gap. However, the waves spread out to some extent into the area beyond the gap.
What is the doppler effect
The apparent change in the frequency of the wave caused by the source of the wave and the observer. As you move further from the source, the waves are larger- lower frequency/pitch.
What is Red Shift?
The doppler effect for light. When an object moving away appears red and close blue.
What is Stephen Hawking’s theory of the Big Bang?
The universe had a definite start from a small, very dense point it is constantly changing, even today.
What is CMBR?
Scientists discovered that there are microwaves coming from every direction in space: this is called the cosmic microwave background radiation, or CMBR for short.
What is Hoyle’s steady state theory?
The Universe didn’t have a beginning. It has always existed and will always exist exactly how it is now.
What is infra-red radiation?
Infrared radiation is a type of electromagnetic radiation, which involves waves rather than particles. It can even pass through the vacuum of space
What is the difference between boiling and evaporation?
Evaporation is when liquids have enough energy to turn to gas and escape. Boiling is when liquid has enough heat energy for the particles to form bubbles in the liquid.
How do you work out a percentage?
You divide the small number by the bigger number. To make it a percentage, you then have to times it by 100.
What is specific heat capacity?
Specific heat capacity is the energy required to raise the temperature of 1kg of a material by 1 degree.
What are the three things that specific heat capacity depend on?
- ) The mass of the object (m)
- ) The temperature change (ΔT)
- ) The material (c) or (s.h.c)
How is heat conducted through a solid?
Particles gain energy and vibrate more and more. They bump into each other, converting heat energy.
How does double glazing work?
The gap between the two panes of glass is filled with air. Heat loss through conduction is reduced, as air is a poor conductor of heat.
What is dry air?
Dry air is air that contains no water vapour.
In which direction does energy flow?
Heat energy flows from warm areas to cold areas.
What are the two types of solar panels?
- ) Solar water heaters
2. ) Photovoltaic cells