The metal returns up the outer cylinder, and electric currents create a magnetic field.

BBC: Planet Earth

Electric currents could convey sound along a wire if they undulated in accordance with the sound waves.

NEWYORKER: In the Air

The Sun's changeable magnetic field is generated at the boundary between these two layers, where strong electric currents flow.

BBC: Sun, Trace

And, solar cells that turn sunlight into electric currents could become more efficient and diminish the global need for carbon-based fuels.

FORBES: Nanotechnology: Expanding Clean Energy and Easing Fuel Shortages

As he reports in Nature this week, Dr Blanke then systematically applied additional electric currents to the woman's right angular gyrus.

ECONOMIST: Out-of-body experiences

Less grimly, electric currents have been used for years by physical therapists to make muscles contract as a way of stimulating and strengthening them.

FORBES: Backrubs From A PDA

Over the course of a week, the electrodes were monitored to find the source of electric currents in the brain responsible for the seizures.

ECONOMIST: Out-of-body experiences

This time I had a "brain pacemaker" installed, which uses wires and a battery source to stimulate deep parts of the brain with electric currents.

CNN: 'I had brain surgery while I was awake'

These are compounds of oxygen, sulphur, selenium and tellurium that are thought to be particularly suitable for thermoelectric applications because their structure allows electric currents to flow while blocking thermal currents.

ECONOMIST: Thermoelectrics

On Thursday, the agency's fisheries and ecology team isolated a 100m area of the river next to Ravensbury Park in Merton and used equipment which generated low voltage electric currents to check how many fish survived.

BBC: NEWS | UK | England | London | Toxic spill in river kills fish