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3 years ago

13

Copper has a specific heat of 0,900 J(g C). How much energy in kJ is needed to raise the temperature of a 700 g block of aluminu

m from 30.7°C to 82,1C?(show your steps)

1 answer:

sashaice [31]3 years ago

4 0

Answer:

32.4 kJ

Explanation:

Given that:

Specific heat capacity fo copper, c = 0.9

Mass of copper, m = 700 g

Temperature change, dθ ;t2 - t1 = (82.1 - 30.7) = 51.4

Energy required, E = mcdθ

E = 700 * 0.9 * 51.4

E = 32382 J

Energy required on kJ

32382 / 1000

= 32.382 kJ

= 32.4 kJ

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2 years ago

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tankabanditka [31]

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Explanation:

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Thus, since the cylinders are made from the same material, they have the same density (ρ). So that;

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⇒ $\frac{M_{A} }{M_{B} }$ = $\frac{4}{1}$

Therefore, $M_{A}$ : $M_{B}$ = 4 : 1

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3 years ago

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