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Explain how different parts of the electromagnetic spectrum are useful in communication and medicine, and why safety precautions are needed for some uses. [6 marks]…
A communication satellite is placed in a geostationary orbit. Explain the conditions needed for this orbit and why it is useful for communication. [6 marks]…
Two identical cans are painted matt black and shiny silver. Explain how a fair experiment could compare their cooling rates and why the surface finish affects the results. [6 marks…
A student uses a trapdoor and electromagnet arrangement to measure the acceleration of free fall. When the electromagnet releases a steel ball, an electronic timer starts. The ball…
A skydiver steps out of a stationary hot-air balloon and falls. Some way down she opens her parachute, and eventually lands safely. Describe and explain the motion of the skydiver…
The graph of binding energy per nucleon against nucleon number rises steeply, peaks near iron, and then falls slowly. Using the idea of binding energy per nucleon, explain why ene…
Describe how you would accurately determine the density of a small, irregularly shaped stone using standard laboratory equipment. Your answer should explain which measurements you…
Astronomers observe a distant galaxy and measure the wavelength of a specific hydrogen spectral line to be 660 nm. The same hydrogen line, when observed in a laboratory on Earth, h…
Discuss how the photoelectric effect provides evidence for the particulate nature of electromagnetic radiation, and explain why the wave model of light fails to account for the obs…