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If a train leaves for a 130 mile journey at 1.30pm, and travels at a constant speed of 50 miles per hour, at what time will it arrive?

First, calculate the time taken for the train to complete its journey: Distance = 130, Speed = 50, Time = Distance/Speed = 130/50 = 2.6 hours. Next, use this to calculate the time of arrival: 2.6 hours = 2 h...
LD
Answered by Luke D. Maths tutor
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An excess of Lead (II) oxide reacts with 175cm3 of 1.5 mol dm3 nitric acid. Calculate the maximum quantity of lead that can be obtained from this reaction.

Write the equation: PbO + HNO 3 --> PbNO 3 + H 2 O. Balance the equation: there are two moles of hydrogen (in water) on the right. To balance the hydrogens, two moles of hydrogen are needed on the left to...
HS
Answered by Hibba S. Chemistry tutor
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What are the advantages of making voting compulsory in the UK? (10 Marks)

As evidenced in liberal democracies where compulsory voting is a federal law, this has had a positive impact on political participation and has been proposed by campaigners such as Graham Allen MP so long as...
HD
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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).

Newton's law of gravitation is: F G =(GMm)/(r 2 ).First of all, it's a good idea to draw a diagram of the planet and star, labelling the directions of the centripetal force and and the planet's velocity in p...
JB
Answered by Jake B. Physics tutor
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Write 144 as a product of its prime factors

To do this, we draw a prime factor tree (whiteboard). The easiest way is to keep dividing by 2 (which is a prime number) until we get an odd number. 144/2 = 72 and 72/2 = 36 and 36/2 = 18 and 18/2 = 9 which ...
ES
Answered by Ewan S. Maths tutor
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