Video Transcript
What type of device can be used to
increase the potential difference of electricity supplied to the national grid so as
to increase the power transmitted while reducing the energy lost to the surrounding
environment? A) A solenoid, B) a diode, C) a
capacitor, D) a transformer, E) a rectification circuit.
To solve for the answer, we can
work through what each of these five devices is and what it does. First, a solenoid: a solenoid is a
coil of wire that’s an element of a circuit. When we pass current through a
solenoid, it acts like a magnet. A solenoid creates a magnetic field
within its coils when current runs through it. But it doesn’t increase the
potential difference of electricity in the circuit it’s a part of.
A diode is another type of circuit
element. A diode is designed to let current
pass much more easily through it one way then the other way through the circuit. A diode also doesn’t increase the
potential difference of electricity in the circuit.
Moving on to a capacitor, a
capacitor is a circuit element used for storing up charge and thereby energy. However, the mechanism of the
capacitor means that it can’t add or increase potential difference in the circuit
it’s a part of. This also is not the type of device
we want.
We then consider a transformer. A transformer is a device used to
connect two current loops. In connecting these loops and
varying the number of turns each loop makes around the transformer core, this device
is able to step up or increase or step down or decrease the potential difference or
the voltage in the import or primary current loop. This means that if the potential
difference in the first current loop is 𝑉 one, then the transformer can convert
that potential difference to a different value either higher or lower than 𝑉 one,
depending on the geometry of its setup. A transformer then is exactly the
kind of device used to increase electricity potential difference. This is the device we want to
use.
To round out our list, let’s
consider a rectification circuit. The purpose of a rectification
circuit is often to convert alternating current AC to direct current DC. In that process though, it doesn’t
necessarily increase the potential difference of the electricity running through the
circuit.
All this to say the transformer is
the device we will choose.
