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What is the photoelectric effect? (A-Level Physics)

The photoelectric effect states that electrons are emitted when electromagnetic radiation is shone upon a material. It also provides evidence for the particle-nature of light, since each photon interacts wit...
DD
Answered by Daniel D. • Maths tutor
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Solve the inequality x^2 – 9x – 22 ≥ 0

We are looking for what values of x make this statement true. To start we need to factorise the quadratic.We can do this in two ways, the quadratic formula, or just seeing what numbers work.We'll start with ...
AO
Answered by Adam O. • Maths tutor
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Solve the simultaneous equations: 2x + y = 18 and x - y = 6

Note the following rules for simultaneous equations: 'Same sign subtract' and 'alternate sign add'. The first thing we need to do is find either y or x. To do so here, you add the equations together because ...
MS
Answered by Megan S. • Maths tutor
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x = 0.436363636... . Prove algebraically that x can be written as 24/55.

Let x = 0.436363636... 10x = 4.36363636....1000x = 436.36363636...990x = 432x = 432/990 = 24/55
HJ
Answered by Hoonsoo J. • Maths tutor
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Alice will play 2 games of tennis against Bob. Alice’s chances of winning each game is 0.7. Work out the probability of Alice winning exactly one match.

The chances of Alice winning a game is 0.7, therefore the chances of Bob winning a game is 0.3. To work out the probability of Alice winning exactly one game, the probabilities of Alice winning once and Bob ...
CG
Answered by Charlie G. • Maths tutor
4289 Views