click below
click below
Normal Size Small Size show me how
Physics P1
Important detail for p1
Question | Answer |
---|---|
What evidence is there for the big bang? | The universe is constantly expanding. There are two examples of evidence to suggest the big bang occurred. Firstly , red shift is when stars moved away from us ; light shift towards the red end of the spectrum. Secondly, Cosmic Micro Background Radiation( |
Describe how a vacuum flask keeps a liquid inside it hot? | Plastic cap stops energy transfer by evaporation. Silver inside stops energy transfer by reflection or radiation. Vacuum stops energy transfer by conduction and convection. Glass is a poor conductor so it stop energy transfer by conduction. |
Explain the process of evaporation and condensation in terms of energy transfer? | Some particles will gain enough energy to escape the surface tension.The rate of evaporation increases if the temperature of the liquid decreases. For condensation particles cool down and lose energy. On theother hand , the rate of condensation increase |
Describe how we get electricity | Power stations produce a high voltage. A turbine is going to transfer electricity when its produced. A step up transformer is used to increase the voltage thus reducing the energy loss by using fewer overhead cables. Also , a step down transformer is used |
Describe the energy transfer involved in a bungee jump? | Firstly , gravitational potential energy is stored and then transferred to kinetic energy as we fall (the further we fall the more kinetic energy is being stored) just before we reach the bottom we have the most kinetic energy and then when it starts to s |
Evaluate the ethical and environmental impacts of renewable energy and fossil fuelled power station | An ethical impact of renewable energy is that it takes up land that could be used for food. Another ethical impact is that it destroys habitat. An enviromental advantage of renewable energy is that no pollutants are released;a disadvantage is that it dest |
Describe the way the EM spectrum can be used for communication? | Radio , Microwaves and infrared rays are used for communication. Infrared rays are used in fibre optics which are used for television and internet signals. |
Using examples describe what happens to wasted energy? | In a light bulb the heat energy is wasted and dissipates into the surroundings making it warmer. The more it spreads out the less useful it is. |
magnification | image height/image object |
convex lenses | treat longsighted |
concave lenses | treat shortsighted |
midpoint to top or bottom of transverse wave | amplitude |
top of one peak to top of other peak | wavelength |
frequency | number of waves per second |
transverse waves difference to longitudinal wave | the vibrations are perpendicular to the direction of energy l(oscillations) |
longitudinal wave | parallel to direction of energy of the wave |
convection | when particles are heated and move around they bump into the one next to them and then they space form and then become less dense which causes it to go to the top. When they are the top they are not being heated anymore. They have less energy and there ar |
Doppler Effect | as waves move towards you there is a high frequency and shorter wavelength. As waves move away from you there is a longer wavelength and a shorter frequency |
Red Shift(Evidence of big bang) | It happens when stars move away from us. That means if they are moving away from us they use to in the same place as us. |
Cosmic Micro Background Radiation (Evidence of big bang) | Leftover sound of big bang that is coming from every direction of the universe. |
EM spectrum continued | This is because they travel in long distances. Penultimately microwaves are used in satelliate and TVs.Also they have a shorter wavelenght which means it can carry more information. Furthermore , they have short range and spread less. Radio waves are use |
Radio waves are used in radio communications , they have very long wave lenghts and they can carry radio tv and mobile phones. |