Assignment 28 - Electric Circuits Worksheet 1
Do these exercises on a separate sheet of paper. Show work clearly.
1. Draw a diagram, for the three resistors given below, if the resistances are connected to a 100 V
source and
a. All resistors are in parallel
b. All resistors are in series.
R1 = 20 ohms
R2 = 50 ohms
R3 = 30 ohms
2.
a. What is the current flow through each resistor for problem 1 a?
b. What is the voltage drop across each resistor for problem 1 b?
3. When building a voltmeter, a resistance is placed in series with a movement coil. If the movement
coil of a dc voltmeter has a resistance of 30 ohm and gives a full scale reading with a current of
0.01 A in the coil, what size resistor is needed in order to have the meter read full-scale when
measuring 100 V?
4. The total load (120 V) in a classroom was found to include:
 72 computer monitors at 200 W each
 72 computers at 150 W each
 30 light bulbs at 30 W each
 Note: Each device has 120 V across it.
a. Calculate the equivalent resistance for one of each types of load (1 monitor, 1, computer,
light bulb)
b. What is the current flow through one unit of each type of load?
c. What is the total current flow for the sum of all loads?
d. What is the total load in kilowatts?