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    It would be great if someone talked me through these two questions please
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    10 pwer (watts) = energy over time

    no. kilowatts = cost over cost per kilowatt hour

    use the second equation to find out how many kilowatts she has,
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    FIRST QUESTION

    2.5 x 20 p = 50p
    £2= 50p x 4
    = 4 hours

    I used the 2nd equation - I found out the cost for 1 kwhand then
    I found how many kwh can I do before the £2 runs out . 50p is 1 kwh, £2 is 4.

    sorry if this is wrong or something,did this at the top of my head :-P
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    I still do not understand? Maybe because I am really tired and jones I don't understand the first part.

    (Original post by Meghna96)
    FIRST QUESTION

    2.5 x 20 p = 50p
    £2= 50p x 4
    = 4 hours

    I used the 2nd equation - I found out the cost for 1 kwhand then
    I found how many kwh can I do before the £2 runs out . 50p is 1 kwh, £2 is 4.

    sorry if this is wrong or something,did this at the top of my head :-P
    Why did you do 2.5 x 20p? It says cost per kWh and the 2.5 is 2.5 kW? Not kWh?
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    (Original post by Susta1nz)
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    It would be great if someone talked me through these two questions please
    for question 2)

    think

    what is a kilowatt hour - it is the work done by a 1000 W power output source for an hour

    so if the work done by the wind turbine is 5600kWh over 4 hours, what is the average power output over those 4 hours?

    finish by reading your power output off the graph
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    (Original post by Susta1nz)
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    It would be great if someone talked me through these two questions please
    for 1)

    again, think, a kWh is the work done by a 1000W power output source for 1 hour

    so how much time does it take for a 2,500W power output source to do the equivalent amount of work of 1kWh?

    once you know that, you know for how long £2 can sustain that, given that it is 20p per kWh
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    (Original post by Susta1nz)
    I still do not understand? Maybe because I am really tired and jones I don't understand the first part.



    Why did you do 2.5 x 20p? It says cost per kWh and the 2.5 is 2.5 kW? Not kWh?
    Oh.
    not sure.

    Did this in may last year so its all erased
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    (Original post by boner in jeans)
    for 1)

    again, think, a kWh is the work done by a 1000W power output source for 1 hour

    so how much time does it take for a 2,500W power output source to do the equivalent amount of work of 1kWh?

    once you know that, you know for how long £2 can sustain that, given that it is 20p per kWh
    Oh my gosh, I cannot believe how stupid I can be sometimes. Thank you for help on both of these questions. Amazing Thanks alot
 
 
 
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