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A fluorescent light uses a lining to emit visible light, explain why this is necessary and how it works.

The vapour inside a fluorescent tube is excited and ionised by the electrode either end of the tubes. The excited electrons inside of the vapour are unstable and so decay into lower energy states. The dif...

Answered by Monty C. • Physics tutor

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Find an expression for the escape velocity of a test object.

Escape velocity is the velocity required to just escape the gravitational pull of a body. The gravitational force of a body is given by Newtons Law:
F = GMm / r² (where G is the gra...

Answered by Ciara N. • Physics tutor

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Draw the electric field lines produced by a negative point charge and calculate the electric field strength at a distance of 50mm from a point charge of size -30nC.

The diagram should show a negative point charge with the electric field lines pointing towards the point charge. The separation of the lines should decrease as you get closer to the point charge. The line...

Answered by Jemima B. • Physics tutor

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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).

(Lets consider a simple planetary system composed of a planet orbiting a star. the gravitational force between the two is given by F=(GMm)/(r²). Assuming the planet also moves in a circular orb...

Answered by Karanvir S. • Physics tutor

22225 Views

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

Waves that go up and down in a curvy shape like you would draw on a piece of paper are called transverse waves. Scientifically, these are when the particles move in a direction that is perpendicular (90) ...

Answered by Sarah F. • Physics tutor

9341 Views