physics

1. Magnetic Fields
(2)

2. Review Question
There are 2 magnets with the poles. Determine types of
pole based on this figure …
A B C D

3. How to determine the direction and value of the
magnetic field formed by the presence of an
electric current?

4. Electromagnetism

5. Magnetic Induction
Magnetic Induction is a magnetic
field strength due to an electric
current flowing in a conductor.
Magnetic Field
Magnetic field strength is the
magnitude of the magnetic field
that is formed at certain points
when an electric current is applied
to an intermediary.
Induksi magnetik dapat disamakan pengertiannya dengan medan
magnet
The magnetic field is symbolized by 𝐵 the letter with the SI unit
being Tesla (T)
1 Tesla = 1 Newton/Ampere. Metre

6. .P
>
I
Testing point (titik
uji)
Conductor
How much magnetic force to affect magnetic object
at the test point.
object

7. Right Hand Rule
(RHR)
𝐵 =
𝜇0𝐼
2𝜋𝑑
Where:
B = Magnetic Field (T) or (Wb/𝑚2
)
d = distance between the wire to
a certain point (m)
I = electric current (A)
μo = permeability of free space/air
(4π x 10−7 unit standard, in N/𝐴2
Magnetic Field of a Long
Straight Wire
d

8. Magnetic Field and current
direction of the page
x in to the page
. Out of the page
I I
B
.
P
.
P
B
>
X
B
I
a a
b
Use
RHR

9. a= arah medan magnet tegak lurus terhadap arah bidang
magnetic field line are perpendicular to the plane of the page
b= arah medan magnet dilihat dari dalam bidang
magnetic field line are in the plane of the page

10. E.Q
Determine the direction and magnitude of magnetic
field, B at point A. If the wire having current I is placed
appendicular to a plane.
.A
I=3 A
d= 10 cm
B= 6
𝜇𝑇 direction is in to the page x
x
B

11. E.Q
Tiga buah kawat dengan nilai dan arah arus seperti ditunjukkan gambar
berikut. Tentukan besar dan arah induksi magnet di titik P !

12. 𝐵1 = 0.5 𝑥 10−7 T
𝐵2 = 2 𝑥 10−7 T
𝐵3 = 6 𝑥 10−7
T
𝐵𝑅 = 𝐵1 + 𝐵3 − 𝐵2 =
0.5 𝑥 10−7
T + 6 𝑥 10−7
T −
− 2 𝑥 10−7 T= 4.5 𝑥 10−7 T
x
x
·
x

13. Magnetic Field of a Circular Wire
(for 1 turn and full circular wire)
𝐵 =
𝜇0𝐼
2𝑟
Where:
B = Magnetic Field (T) or
(Wb/𝑚2
)
r = distance to centre, radius
(m)
I = electric current (A)
μo = permeability of free
space/air (4π x 10−7 unit
standard, in N/𝐴2
)
B
I

14. Magnetic Field of a Circular
Wire (another situation)
If any more than 1 turn . The
equation will be:
if the magnetic field due in a
certain angle
𝐵 = 𝑁
𝜇0𝐼
2𝑟
𝐵 =
𝛼
360°
𝜇0𝐼
2𝑟
N= the number
of turn (jumlah
lilitan kawat)
𝛼 =angle formed by
circular wire (sudut
yang dibentuk kawat)

15. E.Q
B=15.7 x 10^-6 T X
I=6A

16. E.Q
Bwire =
Bloop=
Bnet= Bwire+Bloop= …
Direction of Bnet=

17. Exercise
How large and direction of a current flowing in a wire be in order that
the magnetic field at a distance of 0.1 m from the wire 5𝑥10−6
𝑇 ?
<
B
0.1 m
.P

18. Exercise
How large and direction of a current flowing in a wire be in order that
the magnetic field at a distance of 0.1 m from the wire 5𝑥10−6
𝑇 ?
0.1 m
.
A x

19. Exercise
a
I=2A
>

20. Exercise

21. Exercise

22. Exercise

23. The Magnetic Field of
Solenoid
<
U
S
B
B
I

24. Determine the direction of B
>I
>
I

25. Solenoid Magnetic Field Strength in the central position
𝑩 =
𝝁𝟎𝑰𝑵
𝑳
Solenoid Magnetic Field Strength in the end position
𝑩 =
𝝁𝟎𝑰𝑵
𝟐𝑳
Where:
B = Magnetic Field (T) or (Wb/𝑚2
)
L= length of wire (m)
N= Number of turn
I = electric current (A)
μo = permeability of free space/air (4π x 10−7 unit standard, in N/𝐴2
)

26. E. Q