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What is the Doppler effect and how is it exploited in everyday life?

The Doppler effect describes the changes in a wave's frequency (or wavelength) as the source of the wave moves towards/ away from the observer (you). You have almost definitely experienced this phenomenon...

Answered by Abin V. • Physics tutor

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Frank, Mary and Seth shared some sweets in the ratio 4:5:7. Seth got 18 more sweets than Frank. Work out the total number of sweets they shared.

The ratio 4:5:7 is a way of comparing the size of the shares received by Frank, Mary and Seth. It helps to pretend that we are sharing the sweets between some equally-sized boxes: each box has the same nu...

Answered by Richard N. • Maths tutor

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Solve the simultaneous equations “x^2+y^2=4” and “x=2-y”. What does this tell us about the circle centred on the origin, with radius 2, and the straight line with y-intercept 2 and gradient -1?

In order to solve the pair of simultaneous equations, we must find a single set of values for x and y which fulfils both at once. By substituting “x=2-y” into “x²+y²=4”, we obtain a ...

Answered by Aaron D. • Maths tutor

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What is the difference between a longitudinal and a transverse wave?

First it's important to remember that a wave isn't an object that is moving. When a wave moves through a substance the particles of the substance move side to side or backwards and forwards around their o...

Answered by Maya B. • Physics tutor

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