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How might an uncharged object become positively charged? (e.g. AQA Higher specimen paper 1)

Ask student what causes charge, i.e. motion of electrons. So answer is that electrons move away from the object leaving it positively charged, or move onto a neutral object leaving it negatively charged.
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Answered by Joanna W. • Physics tutor
15759 Views

Using the kinetic molecular theory,explain why air pressure inside a syringe increases if the volume decreases from 15.0 cm

In order to tackle this question a general understanding of the the Kinetic Molecular Theory is required. The theory is based on assumptions of the behaviour of Ideal gases which are: Ideal gases are made up...
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Answered by Emma S. • Physics tutor
22586 Views

How does an optical fibre transfer light?

To understand how an optical fibre transfers light, we must first understand the concept of 'total internal reflection'. Whenever light is refracted from one medium to another, the refractive index of the se...
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Answered by Akshay S. • Physics tutor
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The lamp has an efficiency of 20%. Explain what this means.

20% efficiency means that 20% of the electrical energy going into the lamp is transfered to light, and 80% of the energy is lost/wasted.
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Answered by Bryce P. • Physics tutor
16022 Views

Describe how the forces change on a parachutist while they fall.

It is important to remember that there are four main concepts to keep in mind while thinking about the parachutist. To remember them, it might be helpful to use the acronym GADE: Gravity, Acceleration, Drag,...
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Answered by Nicholas D. • Physics tutor
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