Ammeter in both vanes, the vanes repel each other and the moving vane deflects against the restoring force provided by fine helical springs. The deflection of a moving iron meter is proportional to the square of the current. Consequently, such meters would normally have a non linear scale, but the iron parts are usually modified in shape to make the scale fairly linear over most of its range. Moving iron instruments indicate the RMS value of any AC waveform applied. Moving iron ammeters are commonly used to measure current in industrial frequency AC circuits. In a hot-wire ammeter, a current passes
Becky Measures Becky Measures Becky Measures (born 13 October 1981 in Derbyshire, England), from Bakewell, Derbyshire, is a radio presenter on Peak FM, an independent local radio station in Derbyshire and a professional charity fund-raiser. She held a variety of jobs including being an extra for the locally filmed television series "Peak Practice" before moving into radio. In 2004, Measures, then 23, decided to have a double mastectomy after a genetic test revealed that she had an 80 to 90 per cent risk of developing breast cancer. Both her mother and a cousin, Helen, had suffered from the same illness. To help