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Selecciona los resultados correspondientes a las aproximaciones de las derivadas numéricas en cada versión.

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If the kettle has a power rating of 2000W, how long (in seconds) will it take to boil the kettle?

Does this seem about right?

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How does the energy required to heat the aluminium compare to heating water? Suggest a reason why.

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You put just enough water in your electric kettle to make a cup of tea (raise the temperature from 20°C to 100°C). How much energy, in kJ, does this require?

Assume 1 cup = 250 ml, the density of water is 1 kg/L, and that the heat capacity of water is  4184 J kg-1 K-1

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Calculate the energy required, in kJ, to raise the temperature of a 0.25 kg block of aluminium from 20°C to 100°C.

Take the specific heat capacity of aluminium to be  904 J kg-1 K-1

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What are the SI units of the specific heat capacity?

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What is the main mechanism for heat transfer in the following siutation:

   Using a very bright lamp in a zoo to provide a warm area for animals in their enclosure

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What is the main mechanism for heat transfer in the following siutation:

   Cooling a sports injury by placing an icepack over the bruised area.

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Como é definido “seccionamento” na instalação elétrica?

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Duas esferas idênticas e eletrizadas com cargas elétricas e se atraem com uma força de . Se a carga da primeira esfera aumentar cinco vezes e a carga da segunda esfera for aumentada oito vezes, qual será o valor da força, em newtons, entre elas?

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