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lorasvet [3.4K]

3 years ago

6

A student who weighs 500 newtons climbed the stairs from the first floor to the third floor,15 meters above, in 20 seconds. How

much work did she do

1 answer:

damaskus [11]3 years ago

3 0

Work = (500N)(15m)=7500J Power= (7500J)/(20s) =375 W
Hopefully this helps

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I NEED AT LEAST A LIST OF 10 SONGS OF BEETHOVEN'S<br><br>

DanielleElmas [232]

Answer:

<u>Here are some of the songs of Beethoven's</u>:–

Septet.
Moonlight Sonata.
Pathetique Sonata.
Adelaide (Most popular).
Eroica Symphony.
Fifth Symphony.
Fidelio.
Emperor piano concerto.

3 0

2 years ago

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An automobile tire is inflated with air originally at 10.0°C and normal atmospheric pressure. During the process, the air is com

solong [7]

Answer:

(a) $3.81\times 10^5\ Pa$

(b) $4.19\times 1065\ Pa$

Explanation:

<u>Given:</u>

$T_1$ = The first temperature of air inside the tire = $10^\circ C =(273+10)\ K =283\ K$

$T_2$ = The second temperature of air inside the tire = $46^\circ C =(273+46)\ K= 319\ K$

$T_3$ = The third temperature of air inside the tire = $85^\circ C =(273+85)\ K=358 \ K$

$V_1$ = The first volume of air inside the tire

$V_2$ = The second volume of air inside the tire = $30\% V_1 = 0.3V_1$

$V_3$ = The third volume of air inside the tire = $2\%V_2+V_2= 102\%V_2=1.02V_2$

$P_1$ = The first pressure of air inside the tire = $1.01325\times 10^5\ Pa$

<u>Assume:</u>

$P_2$ = The second pressure of air inside the tire

$P_3$ = The third pressure of air inside the tire
n = number of moles of air

Since the amount pof air inside the tire remains the same, this means the number of moles of air in the tire will remain constant.

Using ideal gas equation, we have

$PV = nRT\\\Rightarrow \dfrac{PV}{T}=nR = constant\,\,\,(\because n,\ R\ are\ constants)$

Part (a):

Using the above equation for this part of compression in the air, we have

$\therefore \dfrac{P_1V_1}{T_1}=\dfrac{P_2V_2}{T_2}\\\Rightarrow P_2 = \dfrac{V_1}{V_2}\times \dfrac{T_2}{T_1}\times P_1\\\Rightarrow P_2 = \dfrac{V_1}{0.3V_1}\times \dfrac{319}{283}\times 1.01325\times 10^5\\\Rightarrow P_2 =3.81\times 10^5\ Pa$

Hence, the pressure in the tire after the compression is $3.81\times 10^5\ Pa$ .

Part (b):

Again using the equation for this part for the air, we have

$\therefore \dfrac{P_2V_2}{T_2}=\dfrac{P_3V_3}{T_3}\\\Rightarrow P_3 = \dfrac{V_2}{V_3}\times \dfrac{T_3}{T_2}\times P_2\\\Rightarrow P_3 = \dfrac{V_2}{1.02V_2}\times \dfrac{358}{319}\times 3.81\times 10^5\\\Rightarrow P_3 =4.19\times 10^5\ Pa$

Hence, the pressure in the tire after the car i driven at high speed is $4.19\times 10^5\ Pa$ .

8 0

2 years ago

What is the correct name for this formula BaCI 2?

KIM [24]

BaCI2 stands for Barium Chloride.

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3 years ago

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A piece of wood is floating in a bathtub. A second piece of wood sits on top of the first piece, and does not touch the water. I

Mashutka [201]

Answer:

the water level remains same

Explanation:

This can be explained by Archimedes's principle which says that the wood will sink if weight of wood is more than the weight of the water displaced with weight equal to the water displaced otherwise the wood will float.

Therefore, buoyancy or the buoyant force is the same as the weight of wood, the weight of the water displaced by wood is also the same as that of the weight of wood.

Thus, we can see that the weight of the wood remains same and so is the level of water.

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2 years ago

How should scalar symbols be written? A. in bold type B. in italic type C. with an arrow on top D. in bold type or with an arrow

Gemiola [76]

D is the correct answer..........

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3 years ago