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Rzqust [24]
3 years ago
13

An energy-efficient water heater draws 4 amps in a 220-volt circuit. It costs $75 more that a standard water heater that draws 1

8 amps in a standard 115-volt circuit. If electricity costs 10 cents per kilowatt-hour, how long would you have to run the efficient water heater to recoup the difference in price? Show your calculations.
Physics
1 answer:
HACTEHA [7]3 years ago
3 0
The answer to the question above is "630.25 hours" which is the time to recoup the difference in the water heater cost. This problem can be solved using a simple algebra equation which stated as (18*115*0.1/1000)x - (4*220*0.1/1000)x = $75. In this formula, x represents the time to recoup the difference in the water heater cost (Calculation: 0.207x-0.088x=75 --> 0.119x = 75 --> x = 630.25)<span>. </span>
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An airplane has wings, each with area A, designed so that air flows over the top of the wing at 265 m/s and underneath the wing
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Answer

given,

Pressure on the top wing = 265 m/s

speed of underneath wings = 234 m/s

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density of air =  1.29 kg/m³

using Bernoulli's equation

 P_1 + \dfrac{1}{2}\rho v_1^2 = P_2 + \dfrac{1}{2}\rho v_2^2

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3 years ago
Two rigid tanks of equal size and shape are filled with different gases. The tank on the left contains oxygen, and the tank on t
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Answer:

The number of oxygen molecules in the left container greater than the number of hydrogen molecules in the right container.

Explanation:

Given:

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where:

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M = molecular mass of the gas

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P=\rho.\frac{RT}{M}

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∴The molecules of oxygen are more densely packed than the molecules of hydrogen in the same volume at the same temperature and pressure. So, <em>the number of oxygen molecules in the left container greater than the number of hydrogen molecules in the right container.</em>

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