Explain why we need to put multimeter in series with resistor to get the current for resistor but in parallel to get the voltage? 5. A lamp is connected to a 120-V line. When the switch is first turned on and the filament is cold, the current through the lamp is 8 A, but this drops quickly to 0.5 A when the filament is hot. By what factor is the lamp's resistance increased due to the change in temperature? 6. Would current of a resistor increase or decrease when we use an ammeter in series with it to measure its current?