The maximum current allowed by a device's power rating is limited by a 25-mA fuse. When the device is connected to a 9-V source, what is the maximum power the device can dissipate? 1-20 Traffic lights are being converted from incandescent bulbs to LED arrays to save operating and maintenance costs.
Typically, each incandescent light uses three 100-W bulbs, one for each color R, Y, G. A competing LED array consists of 61 LEDs with each LED requiring 9 V and drawing 20 mA of current.
There are three arrays per light-R, Y, G. A small city has 1560 traffic signals. Since one light is always on 24/7, how much can a city save in 1 year if the city buys their electricity at 7:2¢ per kWh?