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Citrus2011 [14]

2 years ago

12

Choose the true statements about electric fields and forces. (Choose 3)

1 answer:

aleksley [76]2 years ago

3 0

Answer:

The three best answers are:

Electric fields can be positive or negative (depending on source)

Electric fields can attrace or repel objets (assuming the object is charged)

Electric forces are strongest near the charged object E ∝ 1 / R^2

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A heat engine cycle is executed with steam in the saturation dome. The pressure of steam is 1.1 MPa during heat addition and 0.3

klio [65]

Answer:The highest possible efficiency of this heat engine is 11%

Explanation:

Saturated water temperature at P1, Pressure in Heat addition,

1.1 MPa=185°C +273= 458K

Saturated water temperature at P2, Pressure in Heat rejection,

0.3MPa=133.5°C+ 273=406.5K

The highest possible efficiency of any heat engine is the Carnot efficiency given as

Carnot efficiency, ηmax = 1- (T2/ T1)

1- (406.5K/458K)

1-0.88755=0.112

=11%

8 0

3 years ago

The density of gasoline is 730 kg/m3 at 0°C. Its average coefficient of volume expansion is 9.60 10-4(°C)−1. Assume 1.00 gal of

kipiarov [429]

Answer: 0.4911 kg

Explanation:

We have the following data:

$\rho_{0\°C}= 730 kg/m^{3}$ is the density of gasoline at $0\°C$

$\beta=9.60(10)^{-4} \°C^{-1}$ is the average coefficient of volume expansion

We need to find the extra kilograms of gasoline.

So, firstly we need to transform the volume of gasoline from gallons to $m^{3}$ :

$V=8.50 gal \frac{0.00380 m^{3}}{1 gal}=0.0323 m^{3}$ (1)

Knowing density is given by: $\rho=\frac{m}{V}$ , we can find the mass $m_{1}$ of 8.50 gallons:

$m_{1}=\rho_{0\°C}V$

$m_{1}=(730 kg/m^{3})(0.0323 m^{3})=23.579 kg$ (2)

Now, we have to calculate the factor $f$ by which the volume of gasoline is increased with the temperature, which is given by:

$f=(1+\beta(T_{f}-T_{o}))$ (3)

Where $T_{o}=0\°C$ is the initial temperature and $T_{f}=21.7\°C$ is the final temperature.

$f=(1+9.60(10)^{-4} \°C^{-1}(21.7\°C-0\°C))$ (4)

$f=1.020832$ (5)

With this, we can calculate the density of gasoline at $21.7\°C$ :

$\rho_{21.7\°C}=730 kg/m^{3} f=(730 kg/m^{3})(1.020832)$

$\rho_{21.7\°C}=745.207 kg/m^{3}$ (6)

Now we can calculate the mass of gasoline at this temperature:

$m_{2}=\rho_{21.7\°C}V$ (7)

$m_{2}=(745.207 kg/m^{3})(0.0323 m^{3})$ (8)

$m_{2}=24.070 kg$ (9)

And finally calculate the mass difference $\Delta m$ :

$\Delta m=m_{2}-m_{1}=24.070 kg-23.579 kg$ (10)

$\Delta m=0.4911 kg$ (11) This is the extra mass of gasoline

6 0

4 years ago

Facts about river deltas

ivolga24 [154]

Deltas are complex depositional landforms that develop at the mouths of rivers. They are composed of sediment that is deposited as a river enters a standing body of water and loses forward momentum. Famous deltas include the Mississippi delta in Louisiana and the Nile delta in Egypt.

7 0

3 years ago

About how much time elapses between high tides on the same day?

Pani-rosa [81]

There is about 12 hours

6 0

4 years ago

Earth's gravitational force just got three times stronger! What happens to your weight?

kicyunya [14]

Your "weight" is the name you give to that gravitational force.
So your question actually says:

"Your weight just got three times stronger !
What happens to your weight ?"

8 0

3 years ago