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svet-max [94.6K]

2 years ago

13

how much thermal energy is absorbed by a copper water pipe with a mass of 2.3kg when its temperature is raised from 20.0 to 80.0

?

1 answer:

Sphinxa [80]2 years ago

3 0

Explanation:

q = mCΔt

q = (2.3 kg) (385 J/kg/K) (80.0°C − 20.0°C)

q ≈ 53,000 J

q ≈ 53 kJ

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<u>Explanation:</u>

Length of silicon bar, l = 10 μm = 0.001 cm

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μр = 500 cm^2 / V s

The total current flowing in the bar is the sum of the drift current due to the hole and the electrons.

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J = n qE μn + p qE μp

where, n and p are electron and hole densities.

J = Eq (n μn + p μp)

we know that E = V / l

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or

J = 1.01 $\times$ 10^-9 A / m^2

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I = 1.01 $\times$ 10^-9 $\times$ 0.002 = 2.02 $\times$ 10^-12

So, the current flowing in silicon bar is 2.02 $\times$ 10^-12 A.

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