Flashcards
P2
Flashcards do conjunto (20)
- 1What is the order of the electromagnetic spectrum?Radio waves, microwaves, infrared, visible light, UV, X-rays, gamma
- 2Which types of wave have the lowest frequency?Radio waves
- 3What happens to light when it hits a transparent material?Light is transmitted through it
- 4What happens when light hits a translucent material?Light is partly absorbed, partly transmitted
- 5What happens when light hits a shiny surface?Light is reflected
- 6Which carries the most energy, red or blue light?Blue light
- 7Using the idea of photons, how can we imagine electromagnetic rays?A stream of photons
- 8What is intensity?energy transferred per second per metre squared
- 9What happens to the intensity as the radiation spreads out from the source?It decreases
- 10What are ions?Charged particles, formed when an atom gains/loses electrons
- 11Which end of the electromagnetic spectrum is ionising radiation? (high or low frequency?)high frequency such as gamma
- 12How can ionising radiation harm us? Give examples for UV, X-rays and gamma1. Long-term exposure to X-rays can cause cancers.
2. UV rays damage skin cells
3. Gamma rays can cause cancers and even cell death - 13Name forms of background radiationmedical sources, cosmic rays, nuclear power stations, food and drink, gamma rays from ground, radon gas from ground
- 14How does a microwave oven heat up food?Microwaves absorbed by the food, energy transferred into thermal energy which makes the water particles vibrate
- 15How are microwaves equipped to protect us from the microwaves?Metal sheets and mesh reflect the microwaves back into the oven so they don't harm anything outside
- 16Why is the ozone layer useful to life on Earth?It protects us from the sun's high energy UV radiation. Ozone absorbs UV and splits into oxygen and on free oxygen atom.
- 17Define global warmingAn increase in the worldwide average temperature caused by the greenhouse effect
- 18Name two effects of global warming1. Increase in severe weather
2. Rising sea levels due to melting ice caps - 19How do analogue signals carry information?A sound signal is added to a carrier wave which transports information
- 20How do digital signals send information?By using pulses which are decoded. Information can be stored and processed with no interference.
Informações
- Descrição
- GCSE Physics FlashCards sobre P2, criado por eecavendish em 23-04-2014.
- Criado por
- eecavendish
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