whose resistance was 1.0 ȍ less?
(a) ȍ
(b) WSection 8 - Sample problem: solar panels
8.1 The power output of the Sun is 3.91×10^26 W. At an energy cost of $0.11/kW·h, what is the value of the energy produced by
the Sun in one minute?
$
8.2 The intensity of sunlight at the distance of the Earth's orbit is 1380 W/m^2. An Earth-orbiting satellite has a solar panel that
measures 1.35 m by 4.86 m, which converts solar energy to electrical energy with an efficiency of 26%. In one hour, how
much electrical energy does the panel produce? Assume that the satellite's attitude control jets keep the panel oriented
perpendicular to the incoming sunlight.
J
Section 11 - Sample problem: power transmission
11.1 Power transmission lines often use a form of electric current called alternating current, but in many regions, such as the
Province of Quebec, high-voltage direct-current lines are used instead. Direct current is the kind of electric current you arestudying in this chapter. A certain direct-current power transmission line has a resistance of 0.255 ȍ/km. 812 kV of potential
drives the current from the generating station to a city located 125 km from the plant. What is the power loss due to resistance
in the line?
W