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A matchbox of height h and uniform density stands on its end on a table with coefficient of friction μ. For accelerating it horizontally, at acceleration a, whilst upright, at which height y should the acceleration be applied?

Since the matchbox is of uniform density, the centre of mass is at the centre. In order to accelerate it horizontally, it must have zero resultant moment about the centre of mass, else it will rotate and ...

Answered by Dakshesh D. • PAT tutor

1874 Views

Deduce the main organic product for the reaction of benzene with nitric acid in the prescence of sulfuric acid, and provide a complete mechanism for this reaction. (5 marks)

The answer to this question mostly involves drawing of chemical structures and mechanistic arrows.The organic product is nitrobenzene, which students would draw out as part of the mechanism, but must also...

Answered by Erin B. • Chemistry tutor

3172 Views

How do you structure the response to a question about the changes of a population due to natural selection

Individuals within a species show a wide range of genetic variation. Some individuals will have characteristics more suited for their environment, meaning they are more likely to survive and reproduce. Th...

Answered by Samantha B. • Biology tutor

2664 Views

What is price elasticity of demand?

Price elasticity of demand is often shortened to PED
A PED can be different variations of elastic, inelastic or unit elastic.
What PED is is the responsiveness of demand to a change in price.

Answered by Harry B. • Economics tutor

4171 Views

How do I structure an essay?

All essays should have the same structure- introduction, pro and con paragraphs (weigh the paragraphs by the conclusion you plan to draw on) then a short conclusion. Theme each paragraph with a theory (eg...

Answered by Karima M. • Sociology tutor

4886 Views