In Example 22.6 the length of a \(60 \mathrm{W}, 240 \Omega\) lightbulb filament
was calculated to be \(60 \mathrm{cm}\).
a. If the potential difference across the filament is \(120 \mathrm{V},\) what
is the strength of the electric field inside the filament?
b. Suppose the length of the bulb's filament were doubled without changing its
diameter or the potential difference across it. What would the electric field
strength be in this case?
c. Remembering that the current in the filament is proportional to the
electric field, what is the current in the filament following the doubling of
its length?
d. What is the resistance of the filament following the doubling of its
length?