Solution Manual For Hughes Electrical and Electronic Technology 9th Edition by Edward Hughes John Hiley Keith Brown

Solution Manual For
Hughes Electrical and Electronic Technology 9th Edition by Edward Hughes
John Hiley Keith Brown
systematically, using appropriate methods to reach the correct solution.Logical Reasoning: Mathematics is rooted in logical structures, and students are expected to
demonstrate their ability to apply logic to prove statements or solve problems. This is especially important in subjects like proof-based mathematics.Calculation and Accuracy:
Mathematical exams test a student’s ability to perform accurate calculations and apply mathematical principles in the correct sequence to reach a solution.Understanding of
Concepts: Beyond solving problems, mathematics exams test students’ conceptual understanding of core topics, such as algebra, geometry, calculus, or statistics.3.4.
Preparing for Mathematics ExamsMathematics


Solutions to Exercises
Section One: Electrical Principles
Exercises 1
1. F  ma
F
 a   80  0.4 m/s2
m 200
2. 2 kN
3. F  ma
2
Here the acceleration is that of gravity, i.e. 9.81 m/s
 F  10  9.81  98.1 N
4. 9.81 m/s, 19.62 m/s, 29.43 m/s
5. F  ma

 a    1  10
F 3
 0.1 m/s2
m 10  10 3

v  at
v
 t   5  50 s
a 0.1
6. 625 kN
7. The velocity has no effect on the weight, hence
F  ma  10  9.81  98.1 N
The acceleration requires extra force, hence
F  ma  10  (9.81  3)  128.1 N
2
8. 0.98 m/s downwards
9. (a) F  5  103  300  10  9.81
3


 14 715 N  14.7 kN
90  10
3

(b) W  Fd  14 715   10
60
 221  10 J  221 MJ
6


221  10
6
  61.3 kWh
3.6  10
6


90  10
3
(c) P  Fu  14 715   14 715  25
60  60
 368 000 W  368 kW
(d) W  mu   300  10  25
1 2 1 3 2
2 2

 93.75  10 J  26 kWh
6


10. 16 370 Nm



Exercises 2

, 1. 0.000 005 A  5  106 A  5 A
2. 3 MV
V
3. R   6  10 
I 0.6
4. 40 V

systematically, using appropriate methods to reach the correct solution.Logical Reasoning: Mathematics is rooted in logical structures, and students are expected to
demonstrate their ability to apply logic to prove statements or solve problems. This is especially important in subjects like proof-based mathematics.Calculation and Accuracy:
Mathematical exams test a student’s ability to perform accurate calculations and apply mathematical principles in the correct sequence to reach a solution.Understanding of
Concepts: Beyond solving problems, mathematics exams test students’ conceptual understanding of core topics, such as algebra, geometry, calculus, or statistics.3.4.
Preparing for Mathematics ExamsMathematics




V 240
5. I    0.25 A
R 960
6. 2.9 k
V 240
7. I    28.2  10 A  28.2 kA
3

R 8.5  103
8. 5.1 mA
9. V  IR  22  5  110 V
10. 1 mA, 0.67 mA
V1
11. I  10  0.1 A
R1 100
V 100
R  2   1000   1 k
2
I 0.1
12. 1 k
13. V/V
5

4

3

2

1

I/A
0.2 0.4 0.6 0.8 1.0 1.2

14. R/
1000


800


600


I/mA
10 20 30 40 50 60

15. Q  It  2.5  8  20 C
16. 8 C
17. V  IR  2  40  80 V
18. 212 Nm
Po
 20  10  22 727 W  VI
3
19. (a) P 
i
 0.88

, 22 727
 I  94.7 A
240
(b) W  Pt  22.727  6  136.4 kWh
Cost  136.4  8  1091 p
20. 83.8%, 146 kJ; 67.2 
3
21. 1000 cm has a mass of 1 kg, hence, for the pump
10  9.81  40  9810 W
6
(a) Po  1.5  3
10 60

systematically, using appropriate methods to reach the correct solution.Logical Reasoning: Mathematics is
rooted in logical structures, and students are expected to demonstrate their ability to apply logic to prove
statements or solve problems. This is especially important in subjects like proof-based
mathematics.Calculation and Accuracy: Mathematical exams test a student’s ability to perform accurate
calculations and apply mathematical principles in the correct sequence to reach a solution.Understanding of
Concepts: Beyond solving problems, mathematics exams test students’ conceptual understanding of core
topics, such as algebra, geometry, calculus, or statistics.3.4. Preparing for Mathematics ExamsMathematics

, For motor, P Pump output 9810
 Pump input  
p
o
0.9
 10 900 W
10 900 10 900
and P    12 824 W  12.82 kW

i
0.85
12 824
(b) P  VI  I   26.7 A
480
(c) W  Pt  12.82  8  102.6 kWh
systematically, using appropriate methods to reach the correct solution.Logical Reasoning: Mathematics is rooted in logical structures, and
students are expected to demonstrate their ability to apply logic to prove statements or solve problems. This is especially important in subjects
like proof-based mathematics.Calculation and Accuracy: Mathematical exams test a student’s ability to perform accurate calculations and apply
mathematical principles in the correct sequence to reach a solution.Understanding of Concepts: Beyond solving problems, mathematics exams
test students’ conceptual understanding of core topics, such as algebra, geometry, calculus, or statistics.3.4. Preparing for Mathematics
ExamsMathematics

22. 59.5 , 0.65 p
23. Energy to raise 1 kg of aluminium from 12 °C to 660 °C
 950  (660  12)  615 600 J
Latent heat for 1 kg
 450 000 J
 Heat energy for 1 kg is 615 600  450 000  1 065 600 J
40  1 065 600
(a) Po   11 840 W = 11.84 kW
3600
P 11.84
P  o   13.93 kW

i
0.85
(b) Cost  13.93  8  20  2229 p



Exercises 3

1. Across 2  resistor, V2  IR2  2  2  4 V
Across 3  resistor, V3  IR3  2  3  6 V
Across 5  resistor, V5  IR5  2  5  10 V
Total voltage V  V2  V3  V5  4  6  10  20 V
2. 500 , 0.48 A
V 120
3. R   80 
I 1.5
 R1  R2  R3  30  30  R3
 R3  20 
4. 60 
30
5. VAB   100  30 V
30  70
VBC  VLN  VAB  100  30  70 V
VAC  VLN  100 V
VBN  VBC  70 V
6. 35 V, 5 V, 35 V, 50 V, 10 V
9
7. (a) I6    1.5 A
R6 6
9
I   1.0 A
9
9

I15   0.6 A
15