Answer:
The time taken is 84 seconds, please give the brainliest award would be much appreciated.
 
        
             
        
        
        
Answer:

 is time required to heat to boiling point form initial temperature.
 is time required to heat to boiling point form initial temperature.
Explanation:
Given:
initial temperature of water, 
time taken to vapourize half a liter of water, 
desity of water, 
So, the givne mass of water, 
enthalpy of vaporization of water, 
specific heat of water, 
Amount of heat required to raise the temperature of given water mass to 100°C:



Now the amount of heat required to vaporize 0.5 kg of water:

where:
 mass of water vaporized due to boiling
 mass of water vaporized due to boiling


Now the power rating of the boiler:



Now the time required to heat to boiling point form initial temperature:


 
 
 
        
             
        
        
        
Answer: v = 4.4 m/s
Explanation:
In the absence of friction, the total mechanical energy will be constant
KE₀ + PE₀ = KE₁ + PE₁
0 + mg(6) = ½mv₁² + mg(5)
½mv₁² = mg(6 - 5)
v = √(2g(1)) = 4.4 m/s
 
        
             
        
        
        
The electrostatic force between the two ions is 
Explanation:
The electrostatic force between two charged particle is given by Coulomb's law:

where
 is the Coulomb's constant
 is the Coulomb's constant
 are the two charges
 are the two charges
r is the separation between the two charges
In this problem, the ion of sodium has a charge of

while the ion of chlorine has a charge of

And the distance between the two ions is

Substituting, we find the electrostatic force between the two ions:

where the negative sign simply means that the force is attractive, since the two ions have opposite charge.
Learn more about electrostatic force:
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