p1 - energy resources

What are the primary renewable energy resources mentioned in the notes?

Solar, tidal/wave, wind, geothermal, hydro-electricity, bio-fuel.

How do renewable energy resources compare to fossil fuels regarding availability?

Renewable energy resources will never run out, whereas fossil fuels are finite.

What is a downside of renewable energy resources despite their benefits?

They can still cause environmental damage, such as wind turbines killing birds.

What are two forms of non-renewable energy sources used for transportation?

Petrol and diesel cars, coal burnt for steam trains.

What are some renewable options for heating?

Geothermal heat pump, burning bio-fuels, solar water heaters.

What factors affect the reliability of renewable energy sources?

Some depend on specific environmental conditions like wind and sunlight.

What is required to generate hydroelectricity?

Building a dam to flood a valley which allows turbines to generate electricity.

What are the environmental impacts of hydroelectric dams?

They can cause plant decay that releases CO2 and methane, habitat loss, and may look unsightly.

Why is wave power considered less effective on a large scale?

Waves die out with the wind.

What are the benefits of tidal energy generation?

It can provide lots of energy, produce no pollutant gases, and has low running costs.

What are the drawbacks of tidal energy?

Tidal barrages can stop boats from passing freely and disrupt species migration.

How do biofuels achieve carbon neutrality?

As long as plants are grown at the same rate they are burned, they take in CO2 and give it back when burned.

What are two disadvantages of biofuels?

They require high refinement costs and can contribute to habitat destruction.

What is a major advantage of non-renewable energy sources?

They are reliable and can easily respond to increased energy demands.

What are some environmental issues associated with non-renewables?

They produce pollutant gases like CO2 and methane, which contribute to global warming.

How has the demand for energy changed since the early 20th century?

It has increased initially but began to decrease as appliances become more efficient.

What challenges are preventing the widespread adoption of renewable energy resources?

Profit from fossil fuels, lack of funds for renewable infrastructure, conflicts over locations, and concerns about reliability.

what is kinetic energy?

energy stored in movement e.g an object that doesn’t move has 0 kinetic energy

if we apply a force to a spring, what happens and what do we call it?

the spring will stretch when we apply force to it, this is called extension (e)

what is the relationship between force and extension and what happens if we apply too much force?

force and extension are directly proportional, until too much force is applied and the graph shot up, which is when the spring has met its limit of proportionality

what is gravitational potential energy?

the amount of energy stored due to an object’s height above ground

what is chemical energy?

energy from chemical reactions e.g batteries or using mucles

what is specific heat capacity?

the amount of energy required to increase the temperature of 1kg of a substance by 1 degree

what is a system and what happens when a system changes?

a system is an object or a group of objects you’re looking at, when a system changes that mean energy has been transferred e.g pendulum example

what are the 8 energy stores and what are the 4 ways energy can be transferred?

nuclear

chemical

gravitational

kinetic

elastic

electrostatic

magnetic

thermal

• transferred mechanically, electrically, by radiation or by heating

what happens to energy in a closed system?

neither matter nor energy can enter or leave, net change of total energy is always 0

what are the 2 ways work can be done?

when current flows (work is done/ energy is transferred against resistance) - electrical

or by a force moving an object - mecanical

method for investigating the specific heat capacity of something

• use a mass balance to measure out ur substance, make sure to press 0 or zero error

• record the mass of ur substance

• place a thermometer and an immersion heater inside - provides a steady, known source of electrical energy for heating

• record the starting temp

• wrap beaker/object in insulating foam which reduces unwanted energy transfers

• connect a joulemeter and a powerpack to the immersion heater to read and control the amount of electrical energy being used to heat the substance

• leave for 30 mins, read off amount of joules that passed into the immersion heater and the final temp of the substance/ object

• put it into equation and re-arrange to give shc = change in thermal energy / ,mass x temp change

• shc is measured in J/kg oC

sources of innacuracy in the sshc experiment and how to fix them

thermal energy transfers to surroundings - use an insulator with a lower thermal conductivity

not all thermal energy passing into substance/object - ensure immersion heater is fully submerged

incorrect reading of thermometer - use an electronic temp probe

thermal energy not spread through substance - stir it

describe energy transfers in closed systems

cold spoon dropped into insulated flask of hot soup, thermal energy is transferred to the spoon and then transferred back to the soup, no thermal energy is dissipated as the system is insulated, meaning net change of energy is 0

law of conservation of energy

energy can be transferred usefully, stored of dissipated but it cannot be created or destroyed

what is conduction and convection and what do they occur in?

conduction - when energy is transferred through solids, the particles gain kinetic energy as they vibrate against eachother, transferring energy between eachother

convection - when a liquid/gas is heated, kinetic energy is transferred to the particles, causing them to move quicker and causes the density of the region being heated to inc, as the space between particles increases, the particles will move from hotter to cooler eras

describe what happens in a convection current

• liquid/gas is heated

• particles that recive the most heat inc kinetic energy and rise up above the cooler regions

• eventually cool and fall back down

what is the diference between conduction and convection

in conduction only the energy is transferred but in convection bc of liquids and gasses spread out particles they also move

how can heat or energy be transferred across empty space/ a vaccumm without particles?

radiation! - especially infared radiation, the main wave involved in transferring heat energy, the hotter an object is the more radiation it emits

what does low thermal conductivity mean?

doesn’t transfer energy easily, meaning it’s a good thermal insulator/ good at keeping heat in

how does the home reduce unwanted energy transfers?

• thick walls made of a material with a low thermal conductivity - meaning slower rate of energy transfer, home will cool slower

• cavity wall insulation - made of an inner and outer wall with an air gap in the middle - reduces energy transfer by conduction, can be filled with foam - reduces energy transfer by convection

• loft insulation - fibreglass wool - good insulator and reduces energy t by conduction and reduces energy t by convection currents

• double glazing - two sheets of glass with a air gap in the middle - reduces conduction

• draught excluders - stops hot air leaving by convection

why do we want to reduce friction and how do we do it?

friction can cause wasted energy transfers, as it creates thermal energy which is dissipated to the surroundings e.g air resistance

lubrication reduces frictional forces, oils or streamlining

why do we want devices to be more efficient?

so that less energy is wasted - can improve by insulating, lubricating or streamlining

no device is 100% efficient apart from electric heaters because all the energy in their electrostatic stores is transferred usefully