Running a school physics competition

Abstract

Queries in physicsQ560 (from QZP 61) Why does a circular saw made of paper cut plastic? Q562 (from QZP 61) Some books use 'dynamo' for a DC generator and 'alternator' for an AC generator, whilst others use dynamo to describe anything which induces an EMF by moving a coil relative to a magnetic field. Is either name more definitive?The above items were selected from QZP, a thrice-yearly broadsheet. It is available on subscription at a rate of f2.50per annum (f3 overseas) from the editor, Mr