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White raven [17]
3 years ago
11

How long does it take for a 3.5 kW electric water heater to heat 40 kg of water? from 20 ° C to 75 ° C? The specific heat capaci

ty of water is 4190 J/kgK PLEASE HURRY ITS A TEST​
Physics
1 answer:
iren [92.7K]3 years ago
4 0

Answer:

2633.7 s

Explanation:

From the question,

Heat lost by the water heater = Heat gained by the water

Applying,

P = cm(t₂-t₁)/t.................. Equation 1

Where P = power of the heat, c = specific heat capacity of water, m = mass of water, t₁ = initial temperature, t₂ = final temperature, t = time

make t the subject of the equation

t = cm(t₂-t₁)/P.............. Equation 2

From the question,

Given: c = 4190 J/kgK, P = 3.5 kW = 3500 W, m = 40 kg, t₁ = 20°C, t₂ = 75°C

Substitute these values into equation 2

t = 4190×40(75-20)/3500

t = 9218000/3500

t = 2633.7 s

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3 years ago
What is the level of incidence
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Explanation:

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3 years ago
An object, initially at rest, is subject to an acceleration of 34 m/s^2. How long will it take for that object to reach 3400m ?
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6 0
3 years ago
On a production possibilities curve, any point that falls outside the frontier line is considered
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Explanation:

I hope this helps

5 0
3 years ago
If the bonds in the reactants of Figure 7-3 contained 432 kJ of chemical energy and the bonds in the
Yuri [45]

Answer:

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  • <u>The energy would be absorbed</u>

Explanation:

The <em>energy change </em>during a chemical reation, i.e. the reaction energy, is equal to the chemical energy stored in the<em> bonds of the products </em>less the chemical energy stored in the <em>bonds of the reactants</em>.

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