41. In SI units, the electric current density is measured in amperes per square metre. 42. The base quantities for the analyzer were 200 volts, and 0.5 amperes . 43. The 15 ampere ( A ) sockets were generally given a dedicated 15 A circuit. 44. Starting a car requires considerable cranking amperes , the units by which battery power is measured. 45. That includes a pre-and post-cruise stay at the Ampere Hotel in Paris. 46. For example, No . 12 copper wire carries less than 800 amperes per square centimeter. 47. Lesser known is the relationship between the luminance ( candela ) and current ( ampere ). 48. Significant currents on the order of 8 amperes flow through the ground near the earth points. 49. The smallest branch circuit rating is 15 amperes , used for general purpose receptacles and lighting. 50. Power factor is the ratio of resistive ( or real ) power to volt-amperes .