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Read the text again and then write out a list of 5 questions to the text
Work in pairs. Practice asking and answering questions about the
content of the text
Part III
Choose one of the following articles to summarize
1) Magnetism and electricity
For many centuries, scientists from various parts of the world have
conducted several experiments before they could reach the conclusion on the
relationship between magnetism and electricity. The Danish physicist and
chemist Hans Christian Oersted established that electric current in a wire can
deflect a magnetized compass needle. Thus, he was the first to discover that
electric currents create magnetic fields, a phenomenon that inspired the
development of electromagnetic theory. The English physicist Michael Faraday
went on to explain the relationship between electricity and magnetism further.
According to him, if magnetic fields are changed through a loop of wire, then
electric current will be produced within the wire.
There is a relationship between magnetism and electricity as both use
positive and negative forces. Every atom consists of electrons (negatively
charged particles), protons (positively charged particles), and neutrally charged
neutrons. Just because these two different charges exist in the atom, the
phenomena of magnetism and electricity occurs. Electricity, in its static form, is
nothing but an imbalance of positive and negative charges. When an electron is
moving round the nucleus, a loop of electric current is formed. This in turn,
results in the formation of a magnetic field within the electrical loop. It is
believed that this is the basis of the magnetic properties found in different types
of materials. Electric field is the area surrounding a charged particle, where if
any other charged particle makes an entry, it will experience a force. Magnetic
field is the area surrounding a magnet, where apparent magnetic influence can
be found. Any change in an electric field would result in the formation of a
magnetic field. On the other hand, changing magnetic fields would yield
electric fields.
The noted Scottish physicist and mathematician James Clerk Maxwell
derived some equations to explain the relationship between the properties of
electric and magnetic fields, as well as their geometric relations involving the
circuits. The amount of force exerted on a charged particle in the presence of an
electric and magnetic field was deduced by the Dutch physicist Hendrik
Lorentz. According to his equation, if a particle without any charge is placed in
an electric field or magnetic field, both the fields will not exert any force on the
