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Physics PAT 2017 question 20 https://www2.physics.ox.ac.uk/sites/default/files/page/2011/02/14/pat-2017-paper-42578.pdf

(Unfortunately the question did not fit in the box, but I have provided a link and can add it to the interview)We begin by considering the binary system. As the two stars are identical (i.e. they have equal ...
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Answered by Samuel G. • PAT tutor
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How do I sketch a function from its equation without using my graphical calculator?

When sketching a graph there are some important points to consider - if you can pinpoint these special places on your graph, you will be able to sketch the whole shape of the graph. Intercepts - these are th...
Answered by • PAT tutor
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Derive the mgh approximation for gravitational potential energy.

Newton's law of gravitation -> GPE = GMm/r - GMm/(r+h)GPE = GMm(1/r - 1/(r+h))GPE = GMm(h)/(r(r+h))r >> h -> GPE ~ (m)(GM/r^2)h = mgh
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Answered by Inigo S. • PAT tutor
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Given that during a total solar eclipse the Sun is fully hidden by the Moon, calculate the radius of the Moon. (You may use the following: Solar radius 700,000 km, Sun-Earth distance 150,000,000 km, Moon-Earth distance 400,000 km)

Let's prepare a diagram with the Sun on the right, Moon in the middle and Earth on the left. Their centres are collinear. Moreover, draw right angled triangles such that the right angle opens from the centre...
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Answered by Viktoria N. • PAT tutor
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A matchbox of height h and uniform density stands on its end on a table with coefficient of friction μ. For accelerating it horizontally, at acceleration a, whilst upright, at which height y should the acceleration be applied?

Since the matchbox is of uniform density, the centre of mass is at the centre. In order to accelerate it horizontally, it must have zero resultant moment about the centre of mass, else it will rotate and top...
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Answered by Dakshesh D. • PAT tutor
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