Why do darker skins reduce the chance of skin cancer?
Darker skins absorb UV and let less UV reach underlying tissue.
1 of 8
Why do infrared waves crisp the outside of a potato but microwaves do not?
infrared heats surface only, this causes water to evaporate from surface, making it crispy.
2 of 8
Why do microwave ovens cook faster than ovens?
Microwaves are only absorbed by water/fat. They do not heat a container or oven, they pass through plastic or glass plate. Penetrates food further so less distance needed for conduction.
3 of 8
Explain the problems in dealing with radioactive waste.
long half lives mean so container must not corrode. It must be stored where there is no possibility of it contaminating water supply. They need to monitor levels of radioactivity for long periods of time as acceptable radioactivity levels may change
4 of 8
Why is it unusual for asteroids to be a threat?
Small probability for predicted trajectory to be with the Earth as Earth is so small compared with space. Most asteroids orbit between Mars and Jupiter. Most small asteroids ‘burn up’ in the Earth’s atmosphere before they reach Earth
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Possible actions that could be taken to manage the threat of an asteroid?
Constant monitoring by satellites / scientists. Could be deflected by explosions.Explosion need to be distant to the Earth so the explosion does not damage the Earth.
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Describe the steps that scientists take when using dummies and cars in tests to improve pedestrian safety.
Experiment with collisions on a dummy under controlled conditions. Collect data from this collision. Draw conclusions from this data. Change or recommend changes in design / experiment.
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Why do crumple zones reduce the force on a passenger?
force = change in momentum / time. So a longer collision time means a smaller rate of change of momentum.
8 of 8
Other cards in this set
Card 2
Front
Why do infrared waves crisp the outside of a potato but microwaves do not?
Back
infrared heats surface only, this causes water to evaporate from surface, making it crispy.
Card 3
Front
Why do microwave ovens cook faster than ovens?
Back
Card 4
Front
Explain the problems in dealing with radioactive waste.
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