Topic 4 - Energy, materials, Systems and Devices Flashcards
are fossil fuels are finite or a non finite resource
fossil fuels are a finite resource
how are fossil fuels formed
fossil fuels are formed from the fossilised remains of plants and animals over millions of years
how are coal, oil and gas extracted
coal, oil and gas are extracted through mining and drilling
why are fossil fuels burned
fossil fuels are burned to superheat water under pressure which drives turbine
what does fracking involve
fracking involves drilling into layers of shale rock deep in the earth to release pockets of gas. water, sand and chemicals are injected into a well in order to force gas backup
what are some examples to renewable alternative energy sources to fossil fuels
wind, solar, tidal, biomass, hydroelectric
what are some disadvantages of wind turbines
very loud. damaging to the envirnment. look unnatural. interrupt birds. only work when windy
what are some advantages of wind turbines
low maintenance. clean energy. clean energy. higher winter output. low cost energy
how do photovaltic cells work
light photons hit the PV cell which allows electrons to flow, creating an electric current
what are some advantages of photovaltaic cells
low maintenance. clean energy. relatively low cost
what are some disadvantages of photovaltaic cells
seasonal fluctuations. no power generated at night. complex positioning issues
how does tidal energy work
the rise and fall of the tide forces water through turbines which drive generators to produce electricity
what is hydroelectic power
a very reliable and contrallable energy resource. thr set up costs are financially and environmentally expensive. vast areas need to be flooded to create reservoirs
how are biofuel/biomass created
biofuel and biomass are created from organic matter which is burned to generate power
what are some examples of biomass fuels
food/farm waste, compost and wood chips or compressed pellets
what pecentage of the worlds electricity does nuclear power account for
nuclear power accounts for 11% of the worlds electricity
what is an advantage of nuclear power
nuclear power provided an abundant, reliable supply of clean energy
what is energy
energy is the capacity to do work. it comes in different forms and can be stored. energy can change between forms
what are some examples of stored energy
chemical, mechanical, nuclear, gravitational
what are some examples of motion energy
movement, electricity, heat, sound, light
how is potential energy stored
potential energy is stored in objects, not in motion, that will move once released
what are some examples of potential energy
waves in s reservoir ready to turn a turbine for HEP, pressure in a fire extinguisher
what does kinectic energy involve
kinectic energy involves motion and movement
what is an example of kinectic energy
electricity when travelling through a circuit, heat radiation, sound coming from a speaker, project light, atoms vibrating
what are some examples of mechanical storage
compression, tension, motion
what are some examples of chemical storage
batteries, gases, solid fuel, food
what are some examples of pneumatic systems
they are very accurate and low maintenance
how is movement created
compressed air or gas
what are pneumatics used in
used in industry, for example with mechanical drills and on automated production lines
what might be used, instead of air, to create a powerful system
pumped and compressed liquid
what are hydraulics used in
lifting equipment, car braking systems, fire fighting cutting equipment
what is an advantage of hydroelectric power
hydroelectric power provides a very controllable supply of power
what happens when there is a surplus supply of electricity
when there is a surplus supply of electricty, water is pumped back up to the high level reservoir
in kinectic pumped storage, where is potential energy stored/ when is it used
potential energy is stored in the water at the higher level and is used when demand is high
what kind of energy do flywheels use, in order to reach optimum speed
flywheels use surplus energy to reach optimum speed
what kind of environment do flywheels rotate in
flywheels rotate in a near frictionless environment
how is electrical energy returned when needed, in flywheel energy storage
the motor used to power flywheels becomes a generator which returns the electrical energy when needed
what are Kinectic Energy Recovery Systems used for
Kinectic Energy Recovery Systems are used on vehicles to save fuel
what type of energy can be used to return energy to a battery
kinectic energy can be used to return energy to a battery
what does chemical energy storage include
chemcial energy storange inclused: batteries (electro-chemical), canisters/bottles of gas, flammable gas ahd hydrogen fuel cells
what kind of energy does a battery store
a battery stores chemical energy in a series of cells. each battery has a positive/negative terminal
how many volts is a cell
1.5V
how many volts is a rechargeable cell
1.2V
what are some advantages of alkaline batteries
alkaline batteries are more effiecient and have a higher capacity when compared to traditional lead-acid varieries. more charge can be stored in the same size battery. they hold their charge well
what rechargeable technology pieces is there an exver increasing demand in
portable domestic appliances and power tools. disability and personal transport. hybrid and all eelctrical vehicles. mobile devices
what are flow batteries
flow batteries are large units used to help smooth demand on the National Grid
what type of batteries are super fast charging and very high capacity
sodium and glass batteries
batteries contain toxic chemicals and metals whcih:
leach into the soil and water table. are harmful to wildlife and the natural habitat. need specialist recycling
What can modern materials help solve
Design issues, technical constraints and environmental issues
What are modern materials
New inventions or one that has been relatively recently discovered
What are biodegradable polymers made from
Biodegradable polymers are made from vegetable starches, often corn starch
What different varieties of biodegradable polymers are there
Polylactic scud (PLA) (use in 3D printing filament. Polyhdroxybutyraye (PHB). Polycaprolactone (PCL)
what materials does the Saltwater Brewery use in order to make 100% biodegradable packaging
Wheat and barley
What is polycaprolactone (PCL)
A low temperature hand mouldable polymer
What temperature does polymorph and coolmorph fuse together at
62 degrees (polymorph) and 42 degrees (coolmorph)
What are some advantages of polymorph/coolmorph
They are both biodegradable, non toxic and can be coloured. They are ideal for modelling as can be shaped using hand pressure. They can be reused and re moulded
What is thermoplastic
A plastic that can be melted and used multiple times
What is thermosetting plastic
A plastic that can be melted but not reused
What is flexible MDF
Flexible MDF is a type of wood that allows for the creation of natural curves.
What is flexible MSF commonly used in
Flexible MDF is commonly used in the design of shop fitting and bespoke commercial projects
What are routed or machines grooves used for in flexible MDF
they are used to enable the material to blend
What are some advantages of titanium
It is relatively lightweight, tough, stiff, low density, excellent resistance, it does not react with the human body so it is used for medical appliances
What are fibre optic cables
Fibre optic cables carry light down a thin glass core
What are some uses of fibre optics
Cable TV and broadband infrastructure, medical applications using endoscope to allow doctors to the see the body, run optoelectronics and novelty goods
What are some advantages of liquid crystal displays (LDC)
screens can be very small and lightweight, bespoke monochrome layouts can be achieved, they have low power consumption, they do not emit light, they come in monochrome and full colour versions
What do nanomaterials benefit from
Nanomaterials benefit from their scale and increase surface area
How big are nanomaterials
1-1000 manometers
What is an advantage of metal foam
Metal foam is very lightweight compared to solid metals. They are 100% recyclable
How air pockets made
Air pockets are made by injecting gas into liquid aluminium or titanium
what type of material reacts to an external stimulus, by changing characteristics and properties
smart materials react to an external stimulus
what do self heating polymers react to, which releases a resin in the new crack
self heating polymers react to stress fractures
why are microcapsules of liquid resin ruptured, with self heating polymers
microcapsules of liquid resin are ruptured to bond the polymer back together
what material was designed to avoid stress cracks filling with water
self heating concrete
what material causes steel reinforcements to rust and weaken the structure
water causes steel reinfocements to rust and weaken the structure
what is the process that self heating concrete undergoes when activated
When stress cracks appear in self-healing concrete, water seeps into them rupturing spheres of food and bacteria. The water activates the food and bacteria and the bacteria starts to feed. The result is that calcium carbonate is formed which fills the crack bonding the concrete back together.
what causes a changes of colour in thermochromic dyes
hot and cold temperatures
what are some examples of applications with thermochromic pigments
fever scan strips used on infants. room thermometers. children’s cutlery and crockery. novelty goods and colour changing clothing
what reaction is seen in prescription sunglass lenses
when ultraviolet and photosensitive halide particles react
what are disadvantages of using photochromic particles with
self-darkening glasses
the reaction can take up to 2 minutes to complete. over time the particles can lose their ability to revert to clear
what are photocromatic pigments used for
novelty goods and colour changing paints
which pigment does UV light stimulate particles in
photochromic pigments
what is ninitol
a SMA of nickel and titanium
How is a shape ‘set’ in to the memory of nitinol
The Nitinol is held in the desired shape and heated to a very high temperature / around 540°C
Explain what stimulus is required to return nitinol to its ‘set’ shape,
once deformed
It is reheated to around 70°C / moderate temperature or has an electrical charge sent through it, which triggers the response to change to the ‘set’ shape
what is a commercial use of nitinol
It is used in dentistry for braces and orthodontics
what is quantum tunnelling composite
a polymer that contains billions of metal particles that don’t touch each other. it is an insulator and a semi conductor
what happens wen pressure is applied to quantum tunnelling composite
When pressure is applied to qauntum tunnelling composite it becomes a conductor allowing an electrical signal to flow
how does piezoelectric material work
Subject it to movement or stress and it produces electricity. Attach an electrical signal to it and it moves
when do piezotranducers vibrate
piezotranducers vibrate when an electcric signal is sent through the contact
what are piezo tranducers used in
piezo tranducers are used in mobile phones and other small electronic devices and toys
what happens when piezo tranducers are tapped or spoken into
when piezo tranducers are tapped or spoken into they produce a small electrical charge that can be amplified to create sound or trigger a response in a circuit
what can be used to detectc PH levels
litmus paper because it uses compounds found in different varieties of lichen
what are some uses of litmus paper
garden/soil testing, pool water testing, skincare products
