Presentation on theme: "Energy for the Home.. What happens to atoms/matter when it heats up? What is the difference between Heat energy and temperature? Why do some objects."— Presentation transcript:
Energy for the Home.
What happens to atoms/matter when it heats up? What is the difference between Heat energy and temperature? Why do some objects take longer to heat up than others? If a room is at 19 O C and a cup of hot chocolate is at 45 O C, what will happen to the heat energy and the temperatures?
This graph shows the temperature of water as it is heated from ice with constant heat source. Explain in detail what is happening at each stage of the graph. Include the key terms: ‘specific latent heat’ and ‘specific heat capacity’.
What are the 3 ways in which heat is transferred? Explain how heat is transferred for each method using examples. What is the best method for stopping each of the 3 types of heat transfer? Looking at the picture of the house, what are some of the methods used to stop heat loss. How do they work? If wall insulation cost £2000 to install and will save you £150 in heating bills, what is the payback time?
Fill in the blanks to in the table below about efficiency. Give some examples of wasted energy from each of the types of heating from above. Heating system Total energy input (J) Useful energy output (J) Efficiency Electric heater % Gas central heating Wood fire120040%
What are the properties of microwaves and infrared waves? What are the similarities and differences of infrared and microwaves? How are these waves used to cook food? In what was are these ways used to communicate?
Which signal is digital and which is analogue? Describe how analogue and digital signals are different. Why is a digital signal considered better? What is multiplexing on a digital signal?
Fibre optic cables use total internal reflection (TIR). Explain what happens inside a fibre optic cable. Use the key terms: Critical angle. Refraction. Reflection. Medium / Material. You should also use diagrams in your explanation.
Wireless communication. List as many forms of wireless communication as you can. What kind of wave does each type use? How does refraction help wireless signals? Explain with the aid of diagrams How does diffraction help wireless signals? Explain with the aid of diagrams How can long distance waves be helped by reflection?
Explain the following properties of waves: Wavelength. Frequency Amplitude Speed. Crests and troughs. If a wave is travelling at 340 m/s and has a frequency of 100 Hz, how long is it? (v = f λ) What are some ways in which light can be used to communicate?
Lasers!!! What makes lasers special? How is laser used to read a CD? Does a CD store digital or analogue information? Explain.
Ultraviolet (UV) waves are considered dangerous, why is this? What can UV cause in humans? What is the natural protection on earth from UV rays?
2 main kinds of waves exist in earthquakes (P-waves and S-waves). Describe in as much detail as you can these two types of waves.