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Using Newton's law of universal gravitation, show that T^2 is proportional to r^3 (where T is the orbital period of a planet around a star, and r is the distance between them).

Newton's law of gravitation is: F G =(GMm)/(r 2 ).First of all, it's a good idea to draw a diagram of the planet and star, labelling the directions of the centripetal force and and the planet's velocity in p...
JB
Answered by Jake B. Physics tutor
5264 Views

Write 144 as a product of its prime factors

To do this, we draw a prime factor tree (whiteboard). The easiest way is to keep dividing by 2 (which is a prime number) until we get an odd number. 144/2 = 72 and 72/2 = 36 and 36/2 = 18 and 18/2 = 9 which ...
ES
Answered by Ewan S. Maths tutor
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What causes the aggregate demand curve to shift?

Aggregate demand is the total demand for all goods and services in an economy; it is essentially gross domestic product. Its components are consumption, investment, government spending and net exports (expor...
JW
Answered by James W. Economics tutor
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Solve x2 + 2x − 4 = 0 leave in simplest form.

This is a Quadratic equation so you would try to factorise.If it was on the calculator paper use the equation (You don't need to memories this equation, but you have to be commutable using it).However this i...
MN
Answered by Malee N. Maths tutor
5300 Views

Explain the differences between the 'passé composé' and the 'imparfait', and the circumstances in which each tense would normally be used.

In French, the 'passé composé' is used to describe actions which have already been completed in the past (which have finished). These include events which have only occurred one time ( je suis né /j' ai comm...
JS
Answered by Jake S. French tutor
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