Newton’s Second Law of Motion.
Answer:
2500 J
Explanation:
We can solve the problem by using the first law of thermodynamics:

where
Uf is the final internal energy of the system
Ui is the initial internal energy
Q is the heat added to the system
W is the work done by the system
In this problem, we have:
Q = +1000 J (heat that enters the system)
W = +500 J (work done by the system)
Ui = 2000 J (initial internal energy)
Using these numbers, we can re-arrange the equation to calculate the final internal energy:

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The elevations on the Index Contour along with the legend of the map, that allows you read intermediate contour lines, gives you a clear perspective of increasing/decreasing elevation.
Answer:
<em>8hours 45minutes</em>
Explanation:
Amount of heat energy used up by the electric substance = heat gained by the water.
Amount of heat energy used up by the electric substance = Power * Time
heat gained by the water. = mcΔt
m is the mass of the water in kg
c is the specific heat capacity
Δt is the change in temperature
Given parameters
Power = 5kW = 5000W
mass of water m = 500kg
c = 4200J/kgC
Δt = 100°C - 25°C = 75°C
Required
Time taken
Substituting the given parameters into the formula
Pt = mcΔt
5000t = 500*4200*75
5000t = 157,500,000
Divide both sides by 5000
t = 157,500,000/5000
t = 31,500 secs
t = (31,500/3600)hrs
t = 8.75hours
t = 8hours 45minutes
<em>Hence it takes 8hours 45minutes to heat 500 kg of water in the tank from 25c to 100c</em>
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It will depend on the frictional force involved in the two. I think it will take more force in sled.