1. The base on an incandescent lamp with a tungsten filament is marked 120V, 50W. Measurement of the resistance of the lamp on a Wheatstone bridge indicates 22.5 ohms at an ambient temperature of 22 deg C. What is the normal operating temperature of incandescence of the filament if the resistance - temperature coefficient of the tungsten filament is 1/180 at 0 deg C. 2. The branches AB, BC, CD and DA of a Wheatstone bridge have resistances 10 ohms, 40 ohms, 60 ohms and 240 ohms, respectively. A galvanometer is in series with a 100 ohm resistor and the combination is connected at points B and D. A battery of 24V is connected across points A and C. Determine the current that will register in the galvanometer.