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3 years ago

How much energy is required to heat 70 g of water at 20°C to boiling

Physics

1 answer:

choli [55]3 years ago

3 0

Answer:

$Q=23,430J$

Explanation:

Hello,

In this case, since we compute the required energy via:

$Q=mC\Delta T$

Whereas m is the mass which here is 70 g, C the specific heat which for water is 4.184 J/(g°C) and ΔT is the temperature difference which is:

$\Delta T=100-20=80\°C$

Therefore, the energy turns out:

$Q=70g*4.184\frac{J}{g\°C}*80\°C\\ \\Q=23,430J$

Best regards.

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(a) How many fringes appear between the first diffraction-envelope minima to either side of the central maximum in a double-slit

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Answer:

The number of fringe is z = 3 fringes

The ratio is $I = 0.2545I_o$

Explanation:

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The width of the slit is $a = 35.7 \mu m = 35.7 *10^{-6}m$

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From the question we are told that the order of the bright fringe is n = 3

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Where $I_o$ is the intensity of the central fringe

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