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energy source – n [C] something such as oil, coal or the sun, which can be
used to provide power for light, heat, etc.:
We all committed to the development
of clean and renewable energy sources.
load – n [C] an amount of electrical power that is being produced:
Utilities need to prepare grids to handle bigger loads and to boost power from
renewable sources.
protection device – n [C] a device used to keep something safe or
protected:
Using an earth-leakage circuit breaker as the sole protection device
is not permitted.
dry cell – n [C] a type of cell in a dry battery, which contains chemicals
only in solid form:
Manganese dioxide is used primarily in the manufacture of
dry cells.
Match the beginnings and the ends. What do these words
combinations mean? Write a sentence for some of them
1.
to prevent
a)
excess current
2.
to interrupt
b)
resistance
3.
to cause
c)
malfunction
4.
to overcome
d)
electric power
5.
to set up
e)
fire or serious injuries
6.
in case of
f)
a circuit
7.
to consume
g)
overloading
Grammar
Put in passive or active forms of the verbs in the box
An electric circuit… (to be) a path through which electric current… (to
flow). A simple circuit … (contain) a source, a switch, a load and a conductor.
Cell … (to use) as a source to supply electric current. Load … (to be) a light
bulb, which glows when the circuit …(to turn) on. Copper wires … (to use) as
conductors with no insulation. Switch … (to use) to open or close the circuit.
Electric circuits …(to classify) in several ways. Series circuits … (to consist) of
several devices, each of them linked up one after another in just a single large
loop. In parallel circuit, different devices … (to arrange) so that a single source
supplies voltage to separate loops of wire. Two of the basic laws that
mathematically describe the performance of electric circuits … (to be) Ohm’s
law and Kirchhoff’s rules. The flow or movement of electrons through the
electrical circuits … (to call) the electric current.
