Recent content by suf7

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    Calculate the molarity of the sodium carbonate solution

    is molarity = moles over volume?? so 25cm3 needs to be converted into dm3 by dividing by 1000 then how wud i work out the moles??
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    Calculate the molarity of the sodium carbonate solution

    Pleez Help Me! when a solution of sulphuric acid was standardised the following results were obtained. exactly 5.3g of pure anhydrous sodium carbonate were dissolved in wter and made up to 250cm3 of solution. 25cm3 of this solution were neutralised by 20cm3 of the acid. calculate the molarity...
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    AC Circuit Physics: Voltage vs. Current Relationships

    Physics Help?? In an AC circuit write down the voltage (V) versus current (I) relationships for a resistor, a capacitor and an inductor in terms of agnular frequency (w) and the resistance (R), Capacitance (C) and inductance (L), respectively. From this define capacitive reactance and inductive...
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    Calculating RMS and Peak Values of Electric Fire

    Sorry i don't quite understand what you mean??
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    Calculating RMS and Peak Values of Electric Fire

    Thanks ALOT!..Using your help i worked out the following: {RMS Current} = 4.167A {Peak Voltage} = 339.4V {Peak Current} = 5.893A Do these values seem ok?...If they are ok could i ask another question??..it carries on from the question I've already asked? Thanks
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    Calculating RMS and Peak Values of Electric Fire

    A one bar electric fire has a power rating of 1000W (1kW). If the RMS voltage of the mains is 240V, find the RMS value of the current flowing in the fire and the peak values of current and voltage? Can some one please help me??..Its a past exam question and i don't even know how to start...
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    Calculate U-Value for Glazed Window with 3m^2 Area and 400W Thermal Transmission

    A single glazed window of area 3m^2 transmits 400W when there is a temperature difference of 15C across the glass, What is the U-value of the glass?? Help me, how do i work this out?
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    Calculating Energy Waste of Making 4 Coffee Cups/Day

    wow, it actually looks right??..thanks for your help..so for the final part how would i work out the cost of that energy?..??..i went to the npower website to find out some figures but its all so confusing??
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    Calculating Energy Waste of Making 4 Coffee Cups/Day

    ok so does that mean that the mass of water per cup works out at 0.24kg so the amount of water being wasted evrytime he makes his 2cups is: E = M x C x CIT = 1.92 x 4190 x 78 = 627494.4 j (This is for ONE boiling of the kettle) so that means that in a day the energy being wasted is...
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    Calculating Energy Waste of Making 4 Coffee Cups/Day

    so should i get a cup and measure its weight, then fill it with water and measure the weight again, subtract one from the other and il have the mass of water??..then i should convert the value accordingly??
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    Calculating Energy Waste of Making 4 Coffee Cups/Day

    Thanks...but i don't know how to work out the mass of a cup of water??
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    Calculating Energy Waste of Making 4 Coffee Cups/Day

    Is this the formula??... Energy = M x C x Change in temperature Room temp is roughly 15 C Boiling temp = 100 C So change in temp = 85 C C, specific heat capacity for water = 4190 Not sure about "M" if this is the right formula?
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    Calculating Energy Waste of Making 4 Coffee Cups/Day

    i don't know how to work it out??...what formula should i use??
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    Calculating Energy Waste of Making 4 Coffee Cups/Day

    HI I am really stuck with this question, i don't know what to do with it??..can anyone help??..id like to learn how to solve this question...thanks. A man makes two cups of instant coffee four times a day. On every occasion he fills the kettle up to the 10-cup level. What is the cost of the...
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