Tugas Fisika

1. TUGAS I FISIKA DASAR II
Nama : I Putu Wesa Angga Jaya
NIM : 2108521010
Kelas : A
Program Studi Fisika
Fakultas MAtematika dan Ilmu Pengetahuan Alam
Universitas Udayana
2022

2. 1. In Fig. 22-35, the four particles form a square of edge length a = 5.00 cm and have charges
q1 = +10.0 nC, q2 = -20.0 nC, q3 = +20.0 nC, and q4 = -10.0 nC. In unitvector notation,
what net electric field do the particles produce at the square’s center?
Pembahasan :
Dik :
a = 5,00 cm = 0,05 m
q1 = +10,0 nC
q2 = -20.0 nC
q3 = +20.0 nC
q4 = -10.0 nC
Dit :
Medan magnet di pusat persegi
Jawab :
• Komponen Sumbu x medan listrik di pusat persegi
𝐸𝑥 =
1
4𝜋𝜀0
[
|𝑞1|
(
𝑎
√2
)
2 +
|𝑞2|
(
𝑎
√2
)
2 −
|𝑞3|
(
𝑎
√2
)
2 −
|𝑞4|
(
𝑎
√2
)
2
]
cos 45°
𝐸𝑥 =
2𝑘
𝑎2
[|𝑞1| + |𝑞2| − |𝑞3| − |𝑞4|] cos 45°
𝐸𝑥 =
2𝑘
𝑎2
[|10 𝑛𝐶| + |−20 𝑛𝐶| − |20 𝑛𝐶| − |−10 𝑛𝐶|] cos 45°
𝐸𝑥 =
2𝑘
𝑎2
[0] cos 45°
𝐸𝑥 = 𝟎 𝒏𝑪
• Komponen Sumbu y medan listrik di pusat persegi
𝐸𝑦 =
1
4𝜋𝜀0
[
−
|𝑞1|
(
𝑎
√2
)
2 +
|𝑞2|
(
𝑎
√2
)
2 +
|𝑞3|
(
𝑎
√2
)
2 −
|𝑞4|
(
𝑎
√2
)
2
]
sin 45°
𝐸𝑦 =
2𝑘
𝑎2
[−|𝑞1| + |𝑞2| + |𝑞3| − |𝑞4|] sin 45°
𝐸𝑦 =
2 × 8,99 × 109
(0,05)2
[−|10 𝑛𝐶| + |−20 𝑛𝐶| + |20 𝑛𝐶| − |−10 𝑛𝐶|] sin 45°
𝐸𝑦 =
17,98 × 109
0,0025
[2 × 10−8
𝐶] sin 45°

3. 𝐸𝑦 = 𝟏, 𝟎𝟐 × 𝟏𝟎𝟓
N/C
Jadi medan magnet di pusat persegi adalah 𝑬
⃗⃗ = 𝑬
⃗⃗ 𝒚ĵ = (𝟏, 𝟎𝟐 × 𝟏𝟎𝟓
N/C) ĵ
2. The cube in Figure has the edge length 1.40 m and is oriented as shown in a region of the
uniform electric field. Find the electric flux through the right face if the electric field, in
newtons per coulomb, is given by (a)6.00i (b)−2.00j and (c)−3.00i+400k (d) What is the
total flux through the cube for each field?
Pembahasan
Dik :
Panjang sisi = 1,40 m
Dit :
a. Flux listrik yang melewati sisi kanan jika medan magnet 6,00i
b. Flux listrik yang melewati sisi kanan jika medan magnet -2,00j
c. Flux listrik yang melewati sisi kanan jika medan magnet -3,00i + 400k
d. fluks total yang melalui kubus untuk setiap bidang
Jawab :
a. Flux listrik yang melewati sisi kanan jika medan magnet 6,00i
Misalkan 𝐴 = 𝐴ĵ = (1,4 𝑚)2
ĵ
ɸ = ∮ 𝐸
⃗ . 𝑑𝐴
ɸ = (6,00)î N/C . (1,4 𝑚)2
ĵ
ɸ = 𝟎 N𝒎𝟐
/C
b. Flux listrik yang melewati sisi kanan jika medan magnet -2,00j
Misalkan 𝐴 = 𝐴ĵ = (1,4 𝑚)2
ĵ
ɸ = ∮ 𝐸
⃗ . 𝑑𝐴
ɸ = (−2,00)ĵ N/C . (1,4 𝑚)2
ĵ
ɸ = 𝟑, 𝟗𝟐 N𝒎𝟐
/C
c. Flux listrik yang melewati sisi kanan jika medan magnet -3,00i + 400k

4. Misalkan 𝐴 = 𝐴ĵ = (1,4 𝑚)2
ĵ
ɸ = ∮ 𝐸
⃗ . 𝑑𝐴
ɸ = (−3,00 î + 400 𝑘
̂) N/C . (1,4 𝑚)2
ĵ
ɸ = 𝟎 N𝒎𝟐
/C
d. Fluks total medan seragam melalui permukaan tertutup selalu nol.