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Why does gravitational potential energy have a negative value?

The negative value stems from the definition of gravitiational potential energy which states that it is equal to the work done by the gravitational field moving a body to its given position from infinity. At...
KP
Answered by Kush P. • Physics tutor
4990 Views

What do I need to do for full marks on the question "describe an everyday circumstance where resonance occurs (4 marks)"?

It's important to look at the number of marks awarded for an answer, this can help you structure your answer and think about what will be on the marking scheme. Here a simple statement of an application of r...
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Answered by Lloyd C. • Physics tutor
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What type of radioactive decay reduces the mass number of a nucleus? Explain how it works.

Alpha radiation reduces the mass number of an atom by 4. When an atom's nucleus is unstably large, it emits an alpha particle which consists of two neutrons and two protons. This is called alpha decay. Since...
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Answered by Francis B. • Physics tutor
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Define a geostationary orbit

A geostationary orbit is one that appears in the same location as seen from an observer on earth. This requires three criteria; It's orbital period must be 24 hours The orbit must be above the equator at aro...
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Answered by Jonathan S. • Physics tutor
3309 Views

Please explain how polarisation of waves occurs?

Electromagnetic waves can be imagined by a sinusoidal wave moving up and down, with this movement perpendicular to the direction that they are travelling in. Imagine a sea wave, it moves up and down but also...
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Answered by Tom M. • Physics tutor
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