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A nail of mass 7.0g is held horizontally and is hit by a hammer of mass 0.25kg moving at 10ms^-1. The hammer remains in contact with the nail during and after the blow. (a) What is the velocity of the hammer and nail after contact?

The principle necessary to answer this question is the conservation of linear momentum. This means that the sum of the momentum of the hammer and nail before impact must be equal to the total momentum of the...
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Answered by Caroline S. • Physics tutor
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Solve x^2 + 15x = - 50

x 2 + 15 x + 50 = 0 (rearrange by adding 50 to both sides) (x + 10)(x + 5) = 0 (factorise the quadratic equation) x + 10 = 0 or x + 5 = 0 (for the above to equal zero, at least one of the bracketed terms mus...
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Answered by Julia S. • Maths tutor
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Explain why it can be said that we live on a 'shrinking' planet?

The term 'shrinking' planet is another way of referring to the process of globalisation, or the deepening and strengthening of ties across transnational borders. This manifests itself in two main ways - good...
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Answered by Paul F. • Geography tutor
4001 Views

Explain the difference between marginal returns to factor and returns to scale?


The short-run is defined as the period during which one cannot vary at least one of the factors of production, i.e. at least one factor of production is fixed. The long-run is defined as the period during wh...
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Answered by Julia S. • Economics tutor
8371 Views

Explain the concept of price elasticity of demand? How does one calculate it? What is the relationship between price elasticity of demand and firms’ total revenue?

Price elasticity of demand (PED) is a measure of the responsiveness of demand for a product after a change in that product’s price. It is calculated with the following formula: PED = %change in quantity dema...
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Answered by Julia S. • Economics tutor
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