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2 years ago

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Because of its metabolic processes, your body continually emits thermal energy. Suppose that the air in your bedroom absorbs all

of this thermal energy during the time you sleep at night (8.0 hours). Assume your metabolic rate to be P = 120 J/s. Estimate the temperature change you expect in this air. Let the volume of your room be 36 m2 and Heat capacity of air is 1000 J/kg C.

1 answer:

nirvana33 [79]2 years ago

6 0

Answer:

77.83783 °C

Explanation:

V = Volume of room = 36 m²

c = Heat capacity = 1000 J/kg C

P = Power = 120 J/s = 120 W

t = Time = 8 hours

$\rho$ = Density of air = 1.225 kg/m³

$\Delta T$ = Change in temperature

Density is given by

$\rho=\frac{m}{V}\\\Rightarrow m=\rhoV\\\Rightarrow m=1.225\times 36\\\Rightarrow m=44.1\ kg$

Heat is given by

$Q=mc\Delta T\\\Rightarrow Pt=mc\Delta T\\\Rightarrow \Delta T=\frac{Pt}{mc}\\\Rightarrow \Delta T=\frac{120\times 8\times 3600}{44.4\times 1000}\\\Rightarrow \Delta T=77.83783^{\circ}C$

The temperature change you expected in this air 77.83783 °C

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Solution:

As per the question:

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Answer:

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Explanation:

El índice de refracción entre dos medios se explica mejor entendiendo primero la refracción.

Cuando las olas se mueven de un medio a otro, a menudo experimentan un cambio de dirección con respecto al medio en el que viajan.

Por lo tanto, el índice de refracción se expresa como el seno del ángulo de incidencia dividido por el seno del ángulo de refracción.

El seno del ángulo de incidencia y la refracción utilizados en esta fórmula de índice de refracción se miden respectivamente con respecto a la vertical.

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¡¡¡Espero que esto ayude!!!

English Translation

The light passes from medium A to medium B at an angle of 35 ° with the horizontal border between the two. If the angle of refraction is also 35 °, what is the relative refractive index between the two media?

Solution

The refractive index between two media is best explained by first understanding refraction.

When waves move from one medium to another, they often experience a change in direction with respect to the medium in which they are travelling.

Hence, refractive index is expressed as the sine of angle of incidence dibided by the sine of angle of refraction.

The sine of angle of incidence and refraction used in this refractive index formula are both respectively measured with respect to the vertical.

In this question,

Angle of incidence = 35° to the horizontal = (90° - 35°) to the vertical = 55° to the vertical.

Angle of refraction = 35°

Refractive index between the two media

= (Sin 55°) ÷ (Sin 35°)

= 0.8192 ÷ 0.5736

= 1.428 = 1.43 to 2 d.p.

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