Key points on Edexcel Physics (P1)

Visible light and the solar system Telescopes have allowed a greater detail of planetary bodies to be seen Different telescopes can detect waves from different parts of the EM spectrum Detecting radio/microwaves allows objects not visible to be seen Telescopes contain lenses which change the direction of light rays

The electromagnetic spectrum Microwaves like light, radio or microwaves do not need a medium to travel Wave energy increases as wavelength decreases in the EM spectrum All waves travel at the same speed in a vacuum Some EM waves can be useful(X-rays) and/or harmful (gamma rays)

Universe Telescopes have increased our understanding of the universe Stars go through a life cycle starting with a cloud of dust being pulled together by gravity The big bang theory is the current accepted model that the universe is expanding The red-shift and cosmic microwave background radiation are evidences supporting this theory

Waves and the earth Frequency is the number of waves/vibrations per second (Hertz-Hz). Infrasound have a frequency of <20Hz and Ultrasound >20KHz Some animals use infrasound to communicate. Ultrasound is used in scanning and sonar imaging Seismic waves are produced by earth movements or explosions P-waves (longitudinal) travel faster and have more energy than S-waves(transverse).

Generation and transmission of electricity Non-renewable sources of energy are coal, oil, gas and nuclear Renewable sources of energy are wind, solar, geothermal, waves, tidal, hydro. Electricity is generated by rotating a coil of wire between two magnets. The electricity is transmitted via the national grid (power stations>step-up transformers>pylons>step-down transformers>homes/factories

Energy and the Future Types of include thermal, light, sound electrical, elastic, gravitational, nuclear Energy transfers take place in most devices and appliances. Example; electrical to heat and light Energy is not created to destroyed but transformed into another. The more efficient the device, the more useful energy it transforms. A constant temperature is achieved when input and output energy are balanced.

Tips Read through the question twice and understand what is needed. Start with the question YOU know well NOT always with QUESTION 1 Do not spend more than 10min in a question. Show working/Calculations Read through your answer twice Attempt all questions Good luck