click below
click below
Normal Size Small Size show me how
GCSE Physics P1
Question | Answer |
---|---|
Explain the difference between heat and temperature. What units are they measured in? | Heat is a measure of energy and is measured in Joules. Temperature is a measure of how how an object is and is measured in degrees. |
Why does a graph showing the temperature of a substance as it's heated have 2 flat bits? | One is where the substance is melting and the other is when it is boiling. |
Describe the process that transfers heat energy through a metal rod. What is this process called? | This is called conduction. This is where the vibrating particles pass on extra kinetic energy to nieghbouring particles. |
Describe how the heat from immersion heater is transferred throughout the water in a tank. What is the process called? | This called convection,and it occurs when the more energetic particles move from the hotter region to the cooler region - and takes heat energy with them. |
Explain how solar hot water panels have a matt black surface. | This is to absorb the heat from the sun's rays. |
Explain how the design of a mug could be changed so that it keeps its contents warmer for longer. | Line the mug with a reflective surface to reflect the heat back into the mug and to reduce heat loss through radiation. |
Name four ways that can reduce heat loss from a house, explain how they work. | Loft insulation reduces heat loss through conduction. Double glazing reduces heat loss from conduction. Cavity walls and insulation reduces heat loss through conduction and convection. Draught proofing reduces heat loss through convection. |
What does a thermogram show? | It shows where your house is leaking heat. |
Which is generally more dangerous - low or high frequency EM radition? | The higher frequency of electromagnetic waves, the more dangerous they are. |
Explain what refraction is and how it can disrupt radio signals. | Refraction is where a signal changes direction when they pass through a different material/density. It can disrupt signals by sending the signal away from the reciever dish. |
Describe how microwaves cook food. | They penetrate a few centimetres into the food before being absorbed by water molecules and increasing their kinetic energy. The energy is then conducted and convected to other parts of the food. |
How are lasers used in CD players? |