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At GCSE level, proof questions are relatively rare and largely will all require a similar sort of approach. The difference with A Level is that the syllabus contains more than one method of proof. You wil...

A body in a stationary orbit will always remain above the same point on the planet as it orbits. For a body to be in such an orbit, it must rotate around the planet in the same direction as the spin of...

The first step to solving this problem is to treat it as a normal quadratic equation; if you are struggling with comparing our equation to a normal quadratic, try substituting sin(x) = y into the equat...

At rest there is a difference in the concentration of sodium ions (Na+) across the membrane of the neurone.

Outside the neurone in the extracellular fluid (ECF) the concentration of Na+ i...

Within the muscle fibre tropomyosin is wrapped around actin filaments and it blocks the binding sites for the myosin-heads.

When calcium ion concentration increases, calciu...