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3 years ago

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WhAT is the change IN THE entropy of 2.0kg of h2o molecules when transform at a constant pressure of 1 atm from water at 100 deg

rees celcius to steam at the same tEMPERATURE?

1 answer:

Fynjy0 [20]3 years ago

3 0

Answer:

The entropy change is 45.2 kJ/K.

Explanation:

mass of water at 100 C = 2 kg

Latent heat of vaporization, L = 2260 kJ/kg

Heat is

H = m L

H = 2 x 2260 = 4520 kJ

Entropy is given by

S = H/T = 4520/100 = 45.2 kJ/K

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A child of mass 46.2 kg sits on the edge of a merry-go-round with radius 1.9 m and moment of inertia 130.09 kg m2 . The merrygo-

Vedmedyk [2.9K]

Answer:

The angular velocity is $w_f = 4.503 \ rad/s$

Explanation:

From the question we are told that

The mass of the child is $m_c = 46.2 \ kg$

The radius of the merry go round is $r = 1.9 \ m$

The moment of inertia of the merry go round is $I_m = 130.09 \ kg \cdot m^2$

The angular velocity of the merry-go round is $w = 2.4 \ rad/s$

The position of the child from the center of the merry-go-round is $x = 0.779 \ m$

According to the law of angular momentum conservation

The initial angular momentum = final angular momentum

So

$L_i = L_f$

=> $I_i w_i = I_fw_f$

Now $I_i$ is the initial moment of inertia of the system which is mathematically represented as

$I_i = I_m + I_{b_1}$

Where $I_{b_i}$ is the initial moment of inertia of the boy which is mathematically evaluated as

$I_{b_i} = m_c * r$

substituting values

$I_{b_i} = 46.2 * 1.9^2$

$I_{b_i} = 166.8 \ kg \cdot m^2$

Thus

$I_i =130.09 + 166.8$

$I_i = 296.9 \ kg \cdot m^2$

Thus

$I_i * w_i =L_i= 296.9 * 2.4$

$L_i = 712.5 \ kg \cdot m^2/s$

Now

$I_f = I_m + I_{b_f }$

Where $I_{b_f}$ is the final moment of inertia of the boy which is mathematically evaluated as

$I_{b_f} = m_c * x$

substituting values

$I_{b_f} = 46.2 * 0.779^2$

$I_{b_f} = 28.03 kg \cdot m^2$

Thus

$I_f = 130.09 + 28.03$

$I_f = 158.12 \ kg \ m^2$

Thus

$L_f = 158.12 * w_f$

Hence

$712.5 = 158.12 * w_f$

$w_f = 4.503 \ rad/s$

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A stone was dropped off a cliff and hit the ground with a speed of 136 ft/s. what is the height of the cliff? (use 32 ft/s2 for

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The negative will be __________ to the positive. Therefore, they are pulling __________ each other, and creating and electrical

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Answer:

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Answer:

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top V + v

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