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Using the principle of the conservation of energy, calculate the maximum speed of a ball of 5.0kg that has been dropped from a height of 20m. (Given that the gravitational field strength is equal to 9.8N/kg)

Answer: 20ms -1 The gravitational potential energy before the ball is dropped is equal to mgh. This gives the ball a maximum gravitational potential energy of 5.0kg * 9.8N/kg 20m which is equal to 980 J. At ...
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Answered by Charlie H. • Physics tutor
4090 Views

Given that a light ray enters a glass prism at angle of 50 degrees from the normal and is refracted to an angle of 30 degrees from the normal, calculate the speed of light in glass.

Answer: 1.96 10 8 ms -1 .Snell's law tells us that n 1 sin(x 1 )= n 2 sin(x 2 ) where x is the angle of a light ray from the normal. Air can be assumed to have a refractive index of 1. Therefore, sin(x 1 ) =...
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Answered by Charlie H. • Physics tutor
3780 Views

A right angled triangle has two short sides of lengths 5cm and 12cm respectively. What is the length of the third side?

13cm. Using Pythagoras theorem a^2 +b^2 =c^2 we substitute our two known lengths into the equation to get 5^2 + 12^2=c^2. So now we have c^2= 25+144. So c^2 =169. So c=√169 = 13. Don't forget the units!!! So...
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Answered by Niall C. • Maths tutor
9055 Views

How can I maximise my performance and efficiency in an exam?

Confidence in your mathematical ability and subsequent answers in an exam is key. During an exam you should be confident with the answers that you are giving which can be achieved with steady revision and at...
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Answered by James S. • Maths tutor
3805 Views

How do you approach a question when you first receive it and then go about planning an essay?

Underline key words, ie. if the question is 'What is the significance of women in Of Mice and Men ?' you would underline 'what', 'significance', 'women' and 'Of Mice and Men'. This allows you to keep on task...
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Answered by Sofia S. • English tutor
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