Problem Solving Exercises
1. HOW MANY COULOMBS ARE REPRESENTED BY THESE
AMOUNTS OF ELECTRONS? A. 6.482 X1017
B.
2.46 X 1019
C.
1.24 X 1018
D.
1.628 X 1020
2. A CURRENT OF 7.4 A FLOWS THROUGH A CONDUCTOR.
CALCULATE HOW MUCH CHARGE PASSES THROUGH ANY
CROSS-SECTION OF THE CONDUCTOR IN 20 S.
3. THE CHARGE ENTERING THE POSITIVE TERMINAL OF
AN ELEMENT IS Q = 5SIN4ΠT MC WHILE THE VOLTAGE
ACROSS THE ELEMENT (PLUS TO MINUS) IS V=3COS4ΠT V
.
(A) FIND THE POWER DELIVERED TO THE ELEMENT AT T=
0.3 S.
(B) CALCULATE THE ENERGY DELIVERED TO THE ELEMENT
BETWEEN 0 AND 0.6 S.
4. A LIGHTNING BOLT WITH 10 KA STRIKES AN OBJECT
FOR 15X10-6S. HOW MUCH CHARGE IS DEPOSITED ON THE
OBJECT?
5. FOR THE CIRCUIT SHOWN IN FIGURE 1 BELOW,
CALCULATE THE VOLTAGE V, THE CONDUCTANCE G, AND
THE POWER P.
FIGURE 1
6. IN THE CIRCUIT SHOWN IN FIG. 2, CALCULATE THE
CURRENT I, THE CONDUCTANCE G, AND THE POWER P.
FIGURE 2
7. THE ESSENTIAL COMPONENT OF A TOASTER IS AN
ELECTRICAL ELEMENT (A RESISTOR) THAT CONVERTS
ELECTRICAL ENERGY TO HEAT ENERGY. HOW MUCH
CURRENT IS DRAWN BY A TOASTER WITH RESISTANCE 15
OHMS AT 110 V?
8. A 600-W TV RECEIVER IS TURNED ON FOR 4 H WITH
NOBODY WATCHING IT. IF ELECTRICITY COSTS 10
CENTS/KWH, HOW MUCH MONEY IS WASTED?
9. A BATTERY MAY BE RATED IN AMPERE-HOURS (AH). A
LEAD-ACID BATTERY IS RATED AT 160 AH.
(A) WHAT IS THE MAXIMUM CURRENT IT CAN SUPPLY FOR
40 H?
(B) HOW MANY DAYS WILL IT LAST IF IT IS DISCHARGED AT
1 MA?
10. A LIGHTNING BOLT CARRIED A CURRENT OF 2 KA AND
LASTED FOR 3 MS. HOW MANY COULOMBS
OF CHARGE
WERE CONTAINED IN THE LIGHTNING BOLT?
11. A TELEPHONE WIRE HAS A CURRENT OF 20 X10-6 A
FLOWING THROUGH IT. HOW LONG DOES IT TAKE FOR A
CHARGE OF 15 C TO PASS THROUGH THE WIRE?
12. DETERMINE THE FOLLOWING QUANTITIES FOR THE
GIVEN CIRCUIT.
A. THE
RESISTANCE?
TOTAL
B. THE CURRENT FROM
THE POWER SUPPLY?
C.
THE CURRENT THROUGH EACH RESISTOR?
D.
THE VOLTAGE DROP ACROSS EACH RESISTOR?
E.
THE POWER DISSIPATED IN EACH RESISTOR?
13. DETERMINE THE FOLLOWING QUANTITIES FOR THE
GIVEN CIRCUIT.
F. THE
RESISTANCE?
TOTAL
G. THE CURRENT FROM
THE POWER SUPPLY?
H. THE
CURRENT
THROUGH EACH RESISTOR?
I.
THE VOLTAGE DROP ACROSS EACH RESISTOR?
J.
THE POWER DISSIPATED IN EACH RESISTOR?
II. Given the Resistor Color Coding below
complete the table.
COLOR BANDS
Ohmic
Value
Minimum
Value
Maximum
Value
EXAMPLE: RED, BLUE, RED,
GOLD
2.60 kΩ
2.47 kΩ
2.73 kΩ
1. RED, YELLOW, RED, NO
COLOR
2. BROWN, BLUE, ORANGE,
NO COLOR
3. GREEN, BROWN, RED, NO
COLOR
4.GRAY, GREEN, BLACK,
GOLD
5.BLUE, BROWN, ORANGE,
SILVER
6. GREEN, RED, SILVER
7. RED, BLUE, GOLD
8. BROWN, BROWN, BROWN
9.BLACK, RED, SILVER
10. VIOLET, GRAY, RED,
GOLD
11.YELLOW, ORANGE,
BLACK
12.BLUE, GRAY, RED.
13. GREEN, VIOLET,
ORANGE
14. BLUE, RED, SILVER,
GOLD
15. YELLOW, BROWN, RED
16.BROWN,BLACK, BLACK,
GOLD
17. BROWN, RED, GOLD
18. GRAY, BLUE, RED
19. RED, BROWN, GRAY,
RED
20. PURPLE, RED, BROWN,
SILVER