electricity Flashcards
(41 cards)
Why are metals good
conductors of electricity?
They have free electrons
What is the unit of charge?
Coulomb (C)
What is an electric current?
The rate of flow of charge (The charge
flowing per second)
What is the unit of electric
current?
AMP(A)
What instrument is used to
measure the size of an electric
current?
Ammeter
What is the equation that links
current, charge and time?
Current = Charge/Time or Charge =
Current x Time or Time = Charge/ Current
What is another name for
voltage?
Potential difference (p.d.)
What does the term voltage
mean?
The energy transferred per coulomb of
charge
What is the unit of voltage
(potential difference)?
Volt(V)
What instrument is used to
measure the potential
difference (voltage) across a
component?
Voltmeter
What is the equation that links
voltage, charge and energy
transferred?
Voltage = Energy transferred/ Charge or
Energy transferred = Charge x Voltage
What is meant by electrical
resistance?
The opposition to the flow of charge or the
opposition to the current
What is the unit of resistance?
Ohm (Ω)
A greater length of wire is
added to a circuit. What
happens to the resistance of
the circuit?
The resistance increases
What happens to the current
in a circuit when the
resistance increases (provided
the voltage remains the
same)?
The current decreases
How are the components
connected in a series circuit?
The components are connected end-to-
end, one after the other.
How are the components
connected in a parallel circuit?
The components are connected across
each other
How are the components
connected in a parallel circuit?
The components are connected across
each other
What is a non-renewable
energy resource?
Being used up faster than it is being
replaced
What is a renewable energy
resource?
Being used up as fast as it is being
replaced
In a power station, what is the
job of a turbine?
To convert heat energy into kinetic energy
In a power station, what is the
job of a generator?
To convert kinetic energy into electrical
energy
Name three fossil fuels
Coal, oil, natural gas
What is the national grid?
A network of power stations and cabling
that carries electricity around the country.
