Part A The heater element of a particular 120-V toaster is a 42-m length of nichrome wire, whose diameter is 0.90 mm The resistivity of nichrome at the operating temperature of the toasters 1.3104 Dm If the toaster is operated at a voltage of 120 V, how much power does & draw? O 1900 W O 2200 W O 1800 W 000 O 2100 W 1000 W

Part A The heater element of a particular 120-V toaster is a 42-m length of nichrome wire, whose diameter is 0.90 mm The resistivity of nichrome at the operating temperature of the toasters 1.3104 Dm If the toaster is operated at a voltage of 120 V, how much power does & draw? O 1900 W O 2200 W O 1800 W 000 O 2100 W 1000 W

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter21: Current And Direct Current Circuits

Section: Chapter Questions

Problem 21P

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When a straight wire is heated, its resistance changes according to the equation R = R0 [1 + (T T0)] (Eq. 17.7), where is the temperature coefficient of resistivity. (a) Show that a more precise result, which includes the length and area of a wire change when it is heated, is R=R0[1+(TT0)][1+(TT0)][1+2(TT0)] where is the coefficient of linear expansion. (See Topic 10.) (b) Compare the two results for a 2.00-m-long copper wire of radius 0.100 mm, starting at 20.0C and heated to 100.0C.
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When a straight wire is heated, its resistance changes according to the equation R = R0 [1 + (T T0)] (Eq. 17.7), where is the temperature coefficient of resistivity. (a) Show that a more precise result, which includes the length and area of a wire change when it is heated, is R=R0[1+(TT0)][1+(TT0)][1+2(TT0)] where is the coefficient of linear expansion. (See Topic 10.) (b) Compare the two results for a 2.00-m-long copper wire of radius 0.100 mm, starting at 20.0C and heated to 100.0C.
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Three 60.0-W, 120-V lightbulbs are connected across a 120-V power source, as shown in Figure P18.50. Find (a) the total power delivered to the three bulbs and (b) the potential difference across each. Assume the resistance of each bulb is constant (even though, in reality, the resistance increases markedly with current). Figure P18.50
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