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Question:

starshippiy
starshippiy
Student
College - Freshman

How much time is necessary for a volume of water in a teapot to vaporise? The volume, V=0.60L, the innitial temp, t=9C degrees, the yield, n=60%.

Teapot's electrical resistance, R=60ohms, the network voltage, U=220 V.

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Posted by starshippiy on Monday June 29, 2009 at 2:33 AM and tagged with electrical resistance, network voltage, science, yield.

Answers:

  1. giorgiana1976
    giorgiana1976 Teacher
    Doctorate

    eNotes Editor

    n*W=n*U^2*tau/R=Q=m*c(tf-t0)+m*l

    tf-final temperature

    t0-initial temperature

    tau=(R/n*U^2)*m[c*(tf-t0)+l]

    By substituting the values, the result will be:

    tau=55 minutes

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    Posted by giorgiana1976 on Monday June 29, 2009 at 10:14 AM