Btec Level 2 – Phys 1 Lesson 1 – Forms of Energy

1. Thursday, 07 August 2014 Btec Level 2 – Phys 1Lesson 1 – Forms of Energy Aims of lesson: Know that energy can exist in many different forms Understand where energy is being changed from one form to another Starter Questions Name 9 different forms of energy (K….., H……, S……, L……., E……., G……, C……., N……., E……….) What types of energy are produced by a light bulb? In question 2 what form of energy is wasted?

2. Forms of Energy Kinetic (moving objects) Heat (hot objects) Sound (vibration of air or other medium) Light (from luminous objects) Electricity (flow of electricity along a wire) Gravitational (‘high up’ objects) Chemical (things you ‘burn’ to release heat) Nuclear (atoms that disintegrate to produce heat) Elastic (stretched objects)

3. Energy Changes Objects change energy from one form into another, e.g. Electricity Light (useful) Heat (wasted) Chemical Heat (useful) Light (wasted) Electricity Kinetic (useful) Heat (wasted) Sound (wasted)

4. Draw energy diagrams (like the previous ones) for the following events… • A car engine • A wind turbine • Roller Coaster a the top of a slope • A archer about to shoot an arrow • A battery • A nuclear reactor e.g. Chemical → Car engine→…. (useful) →…. (wasted)

5. Things to do… • Longman FND. Page 176-177, Q 1-9 & ‘Summary’ • Worksheet E5.1 ‘Types of energy;

6. Questions (HT) • The diagram B shows two items that give out both heat and light energy. Name two other things that give out heat and light energy. • Name something that does not use electricity, but produces sound energy. • Explain what would happen to the water molecules in a cup of water as the temperature decreases from 20°C to -20°C. • What would eventually happen to the particles if the temperature continued to decrease? • A person sleeping upstairs has gravitational potential energy. Explain why this energy is called potential energy. • A blown-up balloon has stored energy. What is the form of this energy and how could you release this energy? • What type of energy do both petrol and chocolate have? • Look at the photo. For each form of energy, write down three places in the kitchen where it is being used or stored(a) Gravitational Potential Energy(b) Chemical energy(c) thermal energy(d) electrical energy • Describe the forms of energy a spacecraft would have during a journey from the earth to the moon

7. 7-Aug-14 Module 9 - EnergyLesson 18 – How we generate our Electricity • Starter Questions… • Name two fossil fuels? • Name a renewable fuel? • What sort of power station uses uranium and plutonium? Aims: How electricity is generated from non-renewable fuels Know how a power station produces electricity

8. Coal, oil and gas are called “fossil fuels”. In other words, they were made from fossils. Fuels A “fuel” is something that can be burned to release heat and light energy. The main examples are:

9. Transformer Boiler Turbine Cooling tower Generator Power stations

10. What does each part do? The boiler is where the fuel is burnt to boil water The steam from the boiler is used to turn a turbine The turbine is connected to the generator, which acts like a dynamo – it generates electricity out of movement The steam is cooled down and turned back into water in the cooling tower

11. The main difference is that the nuclear fuel is NOT burnt – it is used to boil water in a “heat exchanger” Nuclear power stations These work in a similar way to normal power stations:

12. Coal, oil and gas Nuclear Advantages of non-renewable fuels Relatively cheap Reliable Relatively easy to find Flexible in meeting demand Don’t produce as much pollution Cheap fuel costs

14. The problems… Power stations using coal, oil, gas or nuclear fuels can certainly whack out the energy, BUT… Problem 1 – Fossil fuels and nuclear sources will RUN OUT Problem 2 – Burning fossil fuels will pollute the atmosphere Problem 3 - Nuclear plants run the risk of contamination and the cost of shutting them down (“decommissioning”) is very high So what’s the solution?

15. 7-Aug-14 Things to do… Questions: (blockbusters) Longman FND, book 1. Page 192-193. Q 1-7 & ‘Summary’ Homework: Worksheet E14.1 ‘Power Stations’

16. Explain how steam is used to generate electricity • What fuels can be used in a power station? • What form of energy (a) goes into, (b) comes out, of a generator • Copy and complete the following sentences…Power stations use _____ to heat water and change it into steam. Steam turns ____, which spin large magnets. Magnets spinning inside a coil of wire produce an ____ current.Electric Fuels Turbines • What harm can power stations do to the environment • How could you reduce this harm?

17. Rollercoasters

22. Rollercoaster Activity – Pass Criteria • You must include… • How the rollercoaster gets up the fist slope.What energy changes are taking place here • What heights are the drops.Why the heights of the drops are different • What energy changes take place as the rollercoaster travelsWhat forms of energy are Useful / wasted? This lesson… • You have design the plans for a rollercoaster. • The rollercoaster construction team need a ‘side view’ of your design. • E.g.

23. Plan… • This lesson…Draft (on one side of A4) show to Mr C • Next lesson…Final copy – once draft has been checked

24. Thursday, 07 August 2014 Module 9 – Energy, Lesson 9Gravitational Energy Aims of lesson: Know how to calculate the energy of an ‘elevated’ object Know how elevated objects store energy Starter Questions What is the energy change as a roller coaster goes down a slope? As the rollercoaster goes down the slope is any other form of energy produced? How does a hydro-electric power station use gravitational energy?

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34. Gravitational Energy The amount of energy an object has depends on three things… • The mass of the object • The height it is lifted • The strength of gravity

35. 1 kg Mass & Weight Mass: The amount of ‘stuff’ in an object. Mass always stays the same (kilograms) Weight: Gravity (a force) pulls on objects (with mass). The force of gravity on an object is its weight. (Newtons) e.g. Weight = mass x gravity (N) = (kg) x (N/kg) Mr Connett has a mass of 74kg. This is the amount of stuff that makes him. Weight = mass x gravity = 74kg x 10 N/kg = 740 N On Earth gravity pulls on each kilogram with a force of 10N

36. Calculation of Gravitational Energy GPE (gravitational potential energy) = Mass x strength of gravity x height GPE (gravitational potential energy) = Weight x height Energy (or Work done) = Force x distance Questions… (1) A force of 100N drags an object 7 m. How much work is done? (2) An object, mass 3Kg is 6 m above the ground. How much potential energy does it have? (3) A force of 6N is used to move an object 1 m. How much work has been done? (4) (a) An object, mass 1kg is 10 m above the ground. How much potential energy does it have this high up? (b) How much energy will it have if is only 0.5 m above the ground? (c) How much energy will it have if it is at ground level? (d) How much energy must it have lost if it falls from the original height, in part a) to the ground?

37. Calculation of Gravitational Energy GPE (gravitational potential energy) = Mass x strength of gravity x height Questions… (1) An object, mass 3Kg is 6 m above the ground. How much potential energy does it have? (2) (a) An object, mass 1kg is 10 m above the ground. How much potential energy does it have this high up? (b) How much energy will it have if is only 0.5 m above the ground? (c) How much energy will it have if it is at ground level? (d) How much energy must it have lost if it falls from the original height, in part a) to the ground? Remember: Gravity = 10 N/kg

38. Calculation of Gravitational Energy Energy (or Work done) = Force x distance (joules) (newton) (metres) • Questions… • (1) A force of 100N drags an object 7 m. How much work is done? • A force of 6N is used to move an object 1 m. How much work has been done? • A car is pushed a distance of 1000 m. The pushing force is 300N, how much energy is used? • 300 Joules of energy was used to move an object. The force was 50N, how far was the object pushed?

40. What is the equation that links force, distance moved in the direction of the force and work done?What are the units of the above equation? • (a) What are the units of work?(b) How much energy is transferred when a crane lifts a load of 5000N through a distance of 30m?(c) When does a force not do any work? • A car follows a lorry up a hill, which would have the most gravitational energy at the top of the hill – explain your answer? • Sue weighs 500 newtons. She dives 4 metres into a swimming pool.a) What is Sue's weight? b) What is her change in height?c) How much gravitational potential energy does she lose? • Work out the gravitational potential energy that these objects have:a) A bird weighing 1 N, perched at the top of a 20 m high tower.b) A football weighing 7 N, kicked 3 m up into the air. • As a bungy jumper falls through the air his gravitational potential energy decreases. a) Sketch a graph to show how his gravitational potential energy changes into kinetic energy during his first fall.Start your graph like this:b) Where does the energy come from to make him bounce back upwards?

41. What is the name of energy that ‘high up’ objects have? • An object has a mass of 3kg, it is lifted 5m, how much energy does it have? • Mr C (mass 75kg) walks up some stairs (10m). How much energy did he use? • What energy does a roller coaster have(a) at the top of a slope(b) at the bottom of a slope • As a roller coaster travels down a slope, energy is wasted as H___ and S____. • At lunchtime Mr C, goes to Torridge Way chippy. Does he have more or less energy at the chip shop, compared to school – why?

42. 1 kg Mass & Weight Mass: The amount of ‘stuff’ in an object. Mass always stays the same (kilograms) Weight: Gravity (a force) pulls on objects (with mass). The force of gravity on an object is its weight. (Newtons) e.g. Weight = mass x gravity (N) = (kg) x (N/kg) Mr Connett has a mass of 74kg. This is the amount of stuff that makes him. Weight = mass x gravity = 74kg x 10 N/kg = 740 N On Earth gravity pulls on each kilogram with a force of 10N

43. Gravitational Energy GPE (gravitational potential energy) = Mass x strength of gravity x height GPE (gravitational potential energy) = Weight x height Recap… • e.g. • A car has a mass of 1200kg. • It dirves up a hill 80 m high. • GPE = Mass x strength of gravity x height = 1200kg x 10 N/kg x 80m = 960000 Joules (J)

44. Gravitational Energy GPE (gravitational potential energy) = Mass x strength of gravity x height GPE (gravitational potential energy) = Weight x height Recap… • e.g. • A car has a mass of 1200kg. • It dirves up a hill 80 m high. • GPE = Mass x strength of gravity x height = 1200kg x 10 N/kg x 80m = 960000 Joules (J) At the top of the hill the car has more gravitational potential energy At the bottom of the hill the car has very little GPE

45. As a bungy jumper falls through the air his gravitational potential energy decreases. a) Sketch a graph to show how his gravitational potential energy changes into kinetic energy during his first fall.Start your graph like this:b) Where does the energy come from to make him bounce back upwards? • A weightlifter lifts a weight of 2250 N above his head.It is lifted a height of 2m, how much work is done? • Mr C has a mass of 73kg(a) What is his weight?(b) If Mr C cycles up Efford lane, his height increases by 70m. How much energy does Mr C use cycling up Efford Lane? • Calculate the gravitational potential energy of a mass of 3509kg that has been lifted by a crane a distance of 20m.The Earth’s gravitational field strength is 10 N/kg • Repeat question 2, but this time the crane is on the moon, where the gravitational field strength is only 1.6 N/kg

46. Calculating Power… Run or walk up stairs (from LSDH to maths floor) – Time taken = ……………s My mass = ………. Kg Energy used to run up stairs = mass (kg) x gravity (10 N/kg) x height (8.5m) = ……… kg x 10 N/kg x 8.5m = ……… J Power = Energy used / Time taken = …………. J / …………s = …………… W (or Joules per second)