2 Eight $7.0\U{W}$ Christmas tree lights are connected in series to each
3 other and to a $110\U{V}$ source. What is the resistance of each
8 Let $V = 110\U{V}$ be the source voltage, $P_1 = 7.0\U{W}$ be the
9 power of one bulb, and $R_1$ be the resistance of one bulb. By
15 And we can find $R_1$ by considering the power dissipated by the bulb
17 P &= IV_1 = I^2 R_1 = \p({\frac{V}{8}})^2\frac{1}{R_1} \\
18 R_1 &= \p({\frac{V}{8}})^2\frac{1}{P} = \ans{27\U{\Ohm}}