Draw a circuit with two identical bulbs and a resistor all placed in parallel with each other and a
battery. Place an ammeter to measure the current coming out of the battery and another ammeter to
measure the current through the resistor. Place a voltmeter to measure the voltage drop around one of
the bulbs. Place a switch that will cut off all current. Place another single switch that will turn off the
current to just the two light bulbs, and place a fuse that if “blown” will shut off all current flow.
Each light bulb consumes 64 watts when a current of 6.0A passes through them. The voltage drop for
the resistor is 20.V when 4.0A flows through the resistor. Determine the current in the circuit, and the
actual power consumed by the light bulb when the switch is closed. The EMF of the battery is 15V. ©2001 Mark D. Greenman
Marblehead Science Matters – mgreenman2@verizon.net
PB#08
printed 9/19/12