Piv txwv ntawm cov lus nug txog hluav taws xob

1. Qhov chaw A nyob deb li ntawm 5 cm ntawm lub zog hluav taws xob ntawm +10 micro Coulombs. Qhov loj thiab kev coj ntawm lub zog hluav taws xob ntawm qhov chaw A yog… (k = 9 x 10⁹ Nm²C^-2, 1 micro Coulomb = 10^-6 C)
Kev Sib Tham
Nws yog paub :

Nug : Qhov loj thiab kev taw qhia ntawm lub zog hluav taws xob ntawm qhov chaw A
Jawb :

Kev taw qhia ntawm lub zog hluav taws xob ntawm qhov chaw A :
Lub zog hluav taws xob yog qhov zoo, yog li ntawd qhov kev taw qhia ntawm lub teb hluav taws xob yog deb ntawm lub zog hluav taws xob thiab deb ntawm qhov chaw A.

2. Qhov nrug ntawm qhov chaw P thiab lub zog ntawm -20 micro Coulombs yog 10 cm. Txheeb xyuas lub zog ntawm lub zog hluav taws xob thiab kev coj ntawm lub zog hluav taws xob ntawm qhov chaw P.
Kev Sib Tham
Nws yog paub :

Nug Qhov loj thiab kev taw qhia ntawm lub zog hluav taws xob ntawm qhov chaw P
Jawb :

Kev taw qhia ntawm lub zog hluav taws xob ntawm qhov chaw A :
Tus nqi hluav taws xob yog qhov tsis zoo, yog li ntawd qhov kev taw qhia ntawm lub teb hluav taws xob yog mus rau tus nqi hluav taws xob thiab deb ntawm qhov chaw P.

3. Ob lub zog fais fab sib cais los ntawm qhov deb ntawm 40 cm. Lub zog fais fab thiab kev coj ntawm lub zog fais fab ntawm qhov chaw nyob hauv nruab nrab ntawm ob lub zog fais fab yog ...

Kev Sib Tham
Xav tias qhov chaw nyob nruab nrab ntawm ob qho nqi yog qhov chaw P.
Nws yog paub :

Nug : qhov loj thiab kev coj ntawm lub zog hluav taws xob ntawm qhov chaw nyob nruab nrab ntawm ob lub nqi (qhov chaw P)
Jawb :
Lub zog hluav taws xob uas tsim los ntawm tus nqi A ntawm qhov chaw P :

Tus nqi A yog qhov tsis zoo yog li ntawd qhov kev taw qhia ntawm lub zog hluav taws xob yog mus rau tus nqi A (mus rau sab laug).
Lub teb hluav taws xob uas tsim los ntawm tus nqi B ntawm qhov chaw P :

Tus nqi B yog qhov zoo yog li qhov kev taw qhia ntawm lub zog hluav taws xob nyob deb ntawm tus nqi B (mus rau sab laug).
Lub zog hluav taws xob tshwm sim ntawm qhov chaw A :
E_A thiab E_B nyob rau hauv tib qho kev taw qhia yog li ntawd lawv raug ntxiv ua ke.
E = E_A Thiab_B
E = (4,5 x 10⁵) + (9 x 10⁵)
E = 13,5 x 10⁵ N / C
Lub zog hluav taws xob ntawm lub zog A mus rau sab laug thiab sab xis (mus rau sab laug).

4. Lub zog hluav taws xob yog xoom ntawm ib qho chaw ntawm qhov deb ntawm ...

Kev Sib Tham
Tus nqi A yog qhov zoo thiab tus nqi B yog qhov zoo, yog li lub zog hluav taws xob yog xoom, nyob hauv nruab nrab ntawm ob tus nqi. Xav tias qhov chaw uas lub zog hluav taws xob yog xoom yog qhov chaw P.
Nws yog paub :

Nug : lub zog hluav taws xob xoom nyob ntawm qhov chaw ntawm qhov deb ntawm…
Jawb :
Lub zog hluav taws xob uas tsim los ntawm tus nqi A ntawm qhov chaw P :

Tus nqi A yog qhov zoo yog li qhov kev taw qhia ntawm lub zog hluav taws xob uas tsim los ntawm tus nqi A ntawm qhov chaw P yog deb ntawm tus nqi A (mus rau sab xis).
Lub teb hluav taws xob uas tsim los ntawm tus nqi B ntawm qhov chaw P :

Tus nqi B yog qhov zoo yog li qhov kev taw qhia ntawm lub zog hluav taws xob uas tsim los ntawm tus nqi B ntawm qhov chaw P yog deb ntawm tus nqi B (mus rau sab laug).
Lub zog hluav taws xob tshwm sim ntawm qhov chaw P = 0 :
E_A thiab E_B kev taw qhia txawv.
E_A - E_B = 0
E_A = E_B

Siv cov qauv ABC los txiav txim siab tus nqi ntawm a.

Lub zog hluav taws xob xoom nyob ntawm qhov chaw 8 cm ntawm tus nqi A lossis 12 cm ntawm tus nqi B.

5. Qhov nrug ntawm ob lub roj teeb A thiab B yog 3 meters. Qhov chaw O nyob nruab nrab ntawm ob lub roj teeb thiab yog 2 meters ntawm lub roj teeb B. q_A = –300 μC thiab q_B = 600 μC. k = 9 × 10⁹ N m² C^-2Lub zog hluav taws xob ntawm qhov chaw O yog cuam tshuam los ntawm tus nqi q_A thiab q_B yog ...
A. 9 × 10⁵ N / C
B. 18 × 10⁵ N / C
C. 52 × 10⁵ N / C
D. 60 × 10⁵ N / C
E. 81 × 10⁵ N / C

Kev Sib Tham:
Nws yog paub :
q_A = –300 μC, q_B = 600 μC, k = k = 9 × 10⁹ N m² C^-2
Nug :
Lub zog hluav taws xob ntawm qhov chaw O yog dab tsi?
Jawb :
Lub zog teb tshwm sim:
E = E_A Thiab_B
E = (2700 x 10³ N/C) + (5400 x 10³ Tsis muaj/C)
E = 8100 x 10³ N / C
E = 81 x 10⁵ N / C
Cov lus teb yog yog E.

6. Ob lub nqi txhua ntawm q₁ = -20 μC thiab q₂ = -40 μC. Yog tias nyob ntawm qhov chaw P uas yog 20 cm ntawm q₂ lub zog hluav taws xob tshwm sim yog xoom, ces tus nqi x yog ...
A. 11 cm
B. 12 cm
C. 13 cm
D. 14 cm
E. 15 cm

Kev Sib Tham:
Nws yog paub :
q₁ = -20 μC, q₂ = -40 μC, r₂ = 0,2 m, r₁ = xwm
Nug :
Qhov deb ntawm qhov P ntawm q₁ (x) ?
Jawb :
Lub zog hluav taws xob tshwm sim yog xoom ntawm qhov chaw P:
Cov lus teb yog D.

7. Qhov chaw A nyob hauv nruab nrab ntawm ob lub nqi hluav taws xob uas muaj tib qhov loj tab sis sib txawv hom sib cais los ntawm qhov deb. Qhov loj ntawm lub zog hluav taws xob ntawm qhov chaw A thaum lub sijhawm ntawd yog 36 NC ^-1 . Yog tias qhov chaw A raug txav mus ze rau ib qho ntawm cov nqi hluav taws xob, ces qhov loj ntawm lub zog hluav taws xob ntawm qhov chaw A tom qab raug txav mus yog ....

A. 100 NC ^-1

B. 96 NC ^-1

C. 80 NC ^-1

D. 60 NC ^-1

E. 16 NC ^-1

Kev Sib Tham

Nws yog paub tias :

Them 1 (q ₁ ) = +Q

Them 2 (q ₂ ) = -Q

Qhov deb ntawm tus nqi 1 thiab qhov taw tes A (r _1A ) = ½ a

Qhov deb ntawm tus nqi 2 thiab qhov taw tes A (r _2A ) = ½ a

Lub zog hluav taws xob ntawm qhov chaw A (EA ₎ = 36 NC ^-1

Lus Nug : Yog tias qhov chaw A raug txav ¼ a ze rau ib qho ntawm cov nqi, ces lub zog hluav taws xob ntawm qhov chaw A yog ...

Lus teb :

Theem 1.

Yuav xam lub zog ntawm lub zog hluav taws xob ntawm qhov chaw A, xav tias muaj lub zog kuaj zoo ntawm qhov chaw ntawd. Qhov muaj lub zog kuaj zoo cuam tshuam rau qhov kev taw qhia ntawm lub zog hluav taws xob.

Lub zog hluav taws xob uas tsim los ntawm tus nqi + Q ntawm qhov chaw A :

Tus nqi kuaj yog qhov zoo thiab tus nqi 1 yog qhov zoo yog li qhov kev taw qhia ntawm lub zog hluav taws xob yog mus rau tus nqi 2.

Lub zog hluav taws xob uas tsim los ntawm tus nqi -Q ntawm qhov chaw A :

Tus nqi kuaj yog qhov zoo thiab tus nqi 2 yog qhov tsis zoo yog li qhov kev taw qhia ntawm lub zog hluav taws xob yog mus rau tus nqi 2.

Lub zog hluav taws xob tshwm sim ntawm qhov chaw A :

Theem 2.

Yog tias qhov chaw A txav mus ze rau qhov them 1 ces:

Qhov nrug ntawm tus nqi 1 thiab qhov taw tes A (r _1A ) = ¼ a

Qhov deb ntawm lub zog them 2 thiab qhov taw tes A (r _2A ) = ¾ a

Lub zog hluav taws xob uas tsim los ntawm tus nqi + Q ntawm qhov chaw A :

Tus nqi kuaj yog qhov zoo thiab tus nqi 1 yog qhov zoo yog li qhov kev taw qhia ntawm lub zog hluav taws xob yog mus rau tus nqi 2.

Lub zog hluav taws xob uas tsim los ntawm tus nqi -Q ntawm qhov chaw A :

Tus nqi kuaj yog qhov zoo thiab tus nqi 2 yog qhov tsis zoo yog li qhov kev taw qhia ntawm lub zog hluav taws xob yog mus rau tus nqi 2.

Lub zog hluav taws xob tshwm sim ntawm qhov chaw A :

Cov lus teb yog C.

8. Ob lub khoom me me uas muaj cov nqi q _A = 1 μC thiab q _B = 4 μC raug muab tso rau 4 cm sib nrug (k = 9 x 10 ⁹ N m ² C ⁻² ). Lub zog hluav taws xob nyob nruab nrab ntawm q _A thiab q _B yog…

A. 6,75 x 10 ⁷ NC ⁻¹

B. 4,50 x 10 ⁷ NC ⁻¹

C. 4,20 x 10 ⁷ NC ⁻¹

D. 3,60 x 10 ⁷ NC ⁻¹

E. 2,25 x 10 ⁷ NC ⁻¹

Kev Sib Tham

Nws yog paub tias :

Them A (q _A ) = 1 μC = 1 x 10 ⁻⁶ C

Them B (qB ₎ = 4 μC = 4 x 10 ⁻⁶ C

k = 9 x 10 ⁹ N m ² C ⁻²

Qhov nrug ntawm cov nqi A thiab B (r _AB ) = 4 cm = 0,04 meters

Qhov nrug ntawm tus nqi A thiab qhov chaw nruab nrab (r _A ) = 0,02 meters

Qhov nrug ntawm tus nqi B thiab qhov nruab nrab (rB ₎ = 0,02 meters

Lo lus nug : Lub zog hluav taws xob nyob nruab nrab ntawm q _A thiab q _B yog…

Lus teb :

Yuav xam lub zog hluav taws xob ntawm q _A thiab q _B , xav tias muaj qhov them nqi kuaj zoo nyob nruab nrab ntawm ob qho nqi. Qhov muaj qhov them nqi kuaj zoo cuam tshuam rau qhov kev coj ntawm lub teb hluav taws xob.

Lub zog hluav taws xob uas tsim los ntawm tus nqi A ntawm nruab nrab :

Tus nqi kuaj yog qhov zoo thiab tus nqi A yog qhov zoo yog li qhov kev taw qhia ntawm lub zog hluav taws xob yog mus rau tus nqi B.

Lub zog hluav taws xob uas tsim los ntawm tus nqi B ntawm nruab nrab :

Tus nqi kuaj yog qhov zoo thiab tus nqi B yog qhov zoo yog li qhov kev taw qhia ntawm lub zog hluav taws xob yog mus rau tus nqi A.

Lub zog hluav taws xob tshwm sim ntawm qhov chaw nruab nrab :

E _A thiab E _B nyob rau hauv qhov kev taw qhia sib txawv.

E = E _B – E _A = 9 x 10 ⁷ – 2,25 x 10 ⁷ = 6,75 x 10 ⁷ NC ^-1

Cov lus teb yog lawm yog A.

9. Saib daim duab hauv qab no ntawm ob lub ntsiab lus them! Qhov chaw P nyob qhov twg kom lub zog hluav taws xob ntawm qhov chaw P sib npaug rau xoom? (k = 9 x 10 ⁹ Nm ² C ⁻² , 1 μC = 10 ⁻⁶ C)

A. nyob nruab nrab ntawm Q ₁ thiab Q ₂

B. 6 cm rau sab xis ntawm Q ₂

C. 6 cm rau sab laug ntawm Q ₁

D. 2 cm rau sab xis ntawm Q ₂

E. 2 cm rau sab laug ntawm Q ₁

Kev Sib Tham

Yuav xam lub zog hluav taws xob ntawm qhov chaw P, xav tias muaj qhov them nqi kuaj zoo ntawm qhov chaw P. Q ₁ yog qhov zoo thiab Q ₂ yog qhov tsis zoo, yog li ntawd qhov chaw P yuav tsum nyob rau sab xis ntawm Q 2 _lossis sab laug ntawm Q _1. Yog tias qhov chaw P nyob rau sab laug ntawm Q ₁ ; lub zog hluav taws xob tsim los ntawm qhov chaw Q ₁ ntawm qhov chaw P yog coj mus rau sab laug (deb ntawm Q ₁ ) thiab lub zog hluav taws xob tsim los ntawm Q ₂ ntawm qhov chaw P yog coj mus rau sab xis (mus rau Q ₁ ). Vim tias qhov kev coj ntawm lub zog hluav taws xob yog qhov sib txawv, ob qho tib si rho tawm ib leeg kom lub zog hluav taws xob ntawm qhov chaw P yog xoom.

Nws yog paub tias :

Q ₁ = +9 μC = +9 x 10 ⁻⁶ C

Q ₂ = -4 μC = -4 x 10 ⁻⁶ C

k = 9 x 10 ⁹ Nm ² C ⁻²

Qhov nrug ntawm tus nqi 1 thiab tus nqi 2 = 3 cm

Qhov nrug ntawm Q ₁ thiab qhov chaw P (r _1P ) = a

Qhov nrug ntawm Q ₂ thiab qhov chaw P (r _2P ) = 3 cm + a

Lo lus nug : Qhov chaw P nyob qhov twg kom lub zog hluav taws xob ntawm qhov chaw P sib npaug rau xoom?

Lus teb :

Point P nyob rau sab laug ntawm Q ₁.

Lub zog hluav taws xob tshwm sim ntawm qhov chaw A :

Siv cov qauv ABC los txiav txim siab tus nqi ntawm a.

10. Saib daim duab hauv qab no! Muab tus nqi q ₃ tso rau ntawm qhov deb ntawm 5 cm ntawm q ₂ , ces lub zog hluav taws xob ntawm tus nqi q ₃ yog… (1 µC = 10 ^-6 C)

A. 4,6 x 10⁷ NC^-1

B. 3,6 x 10 ⁷ NC ^-1

C. 1,6 x 10 ⁷ NC ^-1

D. 1,4 x 10 ⁷ NC ^-1

E. 1,3 x 10 ⁷ NC ^-1

Kev Sib Tham

Tus nqi q ₃ raug tso rau ntawm qhov deb ntawm 5 cm ntawm q ₂ , uas txhais tau tias tsis yog sab laug ntawm q ₂ tab sis sab xis ntawm q _2. Yog tias nws nyob rau sab laug ntawm q ₂ ces lub zog hluav taws xob tshwm sim yog xoom. Qhov no yog vim qhov deb ntawm tus nqi q ₃ thiab tus nqi q ₁ thiab q ₂ yog 5 cm thiab qhov loj ntawm tus nqi q ₁ yog tib yam li tus nqi q ₂.

Vim tias tus nqi q ₃ yog qhov zoo, qhov kev taw qhia ntawm lub zog hluav taws xob ntawm tus nqi q ₃ yog mus rau tus nqi tsis zoo q ₂ (E ₂ ) thiab deb ntawm tus nqi zoo q ₁ (E ₁ ). Lub zog hluav taws xob tshwm sim yog qhov sib sau ua ke ntawm lub zog hluav taws xob E ₁ thiab E ₂.

Nws yog paub tias :

Them q ₁ = 5 µC = 5 x 10 ^-6 Coulomb

Them q ₂ = 5 µC = -5 x 10 ^-6 Coulomb

Qhov nrug ntawm tus nqi q ₁ thiab tus nqi q ₃ (r ₁ ) = 15 cm = 0,15 m = 15 x 10 ^-2 meters

Qhov nrug ntawm tus nqi q ₂ thiab tus nqi q ₃ (r ₂ ) = 5 cm = 0,05 m = 5 x 10 ^-2 meters

k = 9 x 10 ⁹ N m ² C ^-2

Lus Nug : Lub zog hluav taws xob ntawm lub zog them q ₃

Lus teb :

Lub zog hluav taws xob 1

E ₁ = kq ₁ / r ₁ ²

E1 = (9 x 10 ^{9 )} (5 x 10 ^-6 ) / (15 x 10 ^-2 ) ₂

E ₁ = (45 x 10 ³ ) / (225 x 10 ^-4 )

E ₁ = 0,2 x 10 ⁷ N/C

Lub zog hluav taws xob 2

E ₂ = kq ₂ / r ₂ ²

E2 = (9 x 10 ^{9 )} (5 x 10 ^-6 ) / (5 x 10 ^-2 ) ₂

E ₂ = (45 x 10 ³ ) / (25 x 10 ^-4 )

E ₂ = 1,8 x 10 ⁷ N/C

Lub zog hluav taws xob tshwm sim

Lub zog hluav taws xob tshwm sim ntawm tus nqi q ₃ yog:

E = E ₂ – E ₁ = (1,8 x ¹⁰⁷ ) – (0,2 x ¹⁰⁷ ) = 1,6 x 107 ^N /C

Qhov kev taw qhia ntawm lub teb hluav taws xob yog mus rau sab laug lossis hauv qhov kev taw qhia ntawm _E2.

Cov lus teb yog C.

11. Ob lub nqi hluav taws xob raug sib cais raws li qhia hauv daim duab. Lub zog ntawm lub zog ntawm qhov chaw P yog… (k = 9 x 10 ⁹ N m ² C ^-2 )

A. 9,0 x 10⁹ NC^-1

B. 4,5 x 10 ⁹ NC ^-1

C. 3,6 x 10 ⁹ NC ^-1

D. 5,4 x 10 ⁹ NC ^-1

E. 4,5 x 10 ⁹ NC ^-1

Kev Sib Tham

Nws yog paub tias :

Tus nqi q _A = +2,5 C

Tus nqi q _B = -2 C

Qhov nrug ntawm tus nqi q _A thiab qhov chaw P (r _A ) = 5 m

Qhov nrug ntawm tus nqi q _B thiab qhov chaw P (r _B ) = 2 m

k = 9 x 10 ⁹ N m ² C ^-2

Lus Nug : Lub zog ntawm lub zog hluav taws xob ntawm qhov chaw P

Lus teb :

Lub zog hluav taws xob A

EA = kq ^A _/ r _{A 2}

E _A = (9 x 10 ⁹ )(2,5) / (5) ²

EA = ₍ 22,5 x 109 ⁾ / 25

EA = 0,9 x 10 ^{9 N} _/ C

Lub zog hluav taws xob B

E _B = kq _B / r _B ²

E _B = (9 x 10 ⁹ )(2) / (2) ²

E _B = (18 x 10 ⁹ ) / 4

E _B = 4,5 x 10 ⁹ N/C

Lub zog hluav taws xob tshwm sim

Lub zog hluav taws xob tshwm sim ntawm qhov chaw P yog:

E = E _B – E _A = (4,5 – 0,9) x 10 ⁹ = 3,6 x 10 ⁹ N/C

Qhov kev taw qhia ntawm lub teb hluav taws xob yog mus rau sab laug lossis hauv qhov kev taw qhia ntawm E _B.

Cov lus teb yog C.

12. Ob lub zog hluav taws xob, txhua lub muaj Q ₁ = -40 µC thiab Q ₂ = +5 µC, nyob rau hauv qhov chaw raws li pom hauv daim duab (k = 9 x 10 ⁹ Nm ² .C ^-2 thiab 1 µC = 10 ^-6 C), lub zog hluav taws xob ntawm qhov chaw P yog...

A. 2,25 x 10⁶ NC^-1

B. 2,45 x 10 ⁶ NC ^-1

C. 5,25 x 10 ⁶ NC ^-1

D. 6,75 x 10 ⁶ NC ^-1

E. 9,00 x 10 ⁶ NC ^-1

Kev Sib Tham

Nws yog paub tias :

Them q ₁ = -40 µC = -40 x 10 ^-6 C

Them q ₂ = +5 µC = +5 x 10 ^-6 C

Qhov nrug ntawm tus nqi q ₁ thiab qhov chaw P (r ₁ ) = 40 cm = 0,4 m = 4 x 10 ^-1 m

Qhov nrug ntawm tus nqi q ₂ thiab qhov chaw P (r ₂ ) = 10 cm = 0,1 = 1 x 10 ^-1 m

k = 9 x 10 ⁹ N m ² C ^-2

Lus Nug : Lub zog ntawm lub zog hluav taws xob ntawm qhov chaw P

Lus teb :

Lub zog hluav taws xob 1

E ₁ = kq ₁ / r ₁ ²

E1 = (9 x 10 ^{9 )} (40 x 10 ^-6 ) / (4 x 10 ^-1 ) ₂

E ₁ = (360 x 10 ³ ) / (16 x 10 ^-2 )

E ₁ = 22,5 x 10 ⁵ N/C

Lub zog hluav taws xob 2

E ₂ = kq ₂ / r ₂ ²

E2 = (9 x 10 ^{9 )} (5 x 10 ^-6 ) / (1 x 10 ^-1 ) ₂

E2 = (45 x 10 ³ ₎ / 1 x 10 ^-2

E ₂ = 45 x 10 ⁵ N/C

Lub zog hluav taws xob tshwm sim

Lub zog hluav taws xob tshwm sim ntawm qhov chaw P yog:

E = E ₂ – E ₁ = (45 – 22,5) x 10 ⁵ = 22,5 x 10 ⁵ N/C

E = 2,25 x 10 ⁶ N/C

Qhov kev taw qhia ntawm lub teb hluav taws xob yog mus rau sab xis lossis hauv qhov kev taw qhia ntawm _E2.

Cov lus teb yog lawm yog A.

13. Los ntawm daim duab them nqi hauv qab no, uas qhia txog cov kab ntawm lub zog ntawm ob lub them nqi ze ua ke yog ...

Kev Sib Tham

Cov kab hluav taws xob, lossis cov kab ntawm lub zog, raug kos los ntawm lub zog zoo mus rau lub zog tsis zoo. Yog tias lub zog zoo thiab lub zog tsis zoo raug muab tso ze ua ke, cov kab ntawm lub zog yuav tshwm sim zoo li cov lus teb A.

Cov lus teb yog lawm yog A.

8. Ob lub zog hluav taws xob raug coj los ze rau ib leeg hauv ib txoj kab txuas kom lawv thiaj li tsim tau cov kab hluav taws xob. Daim duab tseeb yog...

Kev Sib Tham

Cov lus teb yog D.

9. Cov kab zog kom raug ntawm ob lub nqi yog…

Kev Sib Tham

Cov lus teb yog D.

14. Saib daim duab hauv qab no ntawm ob lub ntsiab lus them nqi!

Qhov chaw P nyob qhov twg kom lub zog hluav taws xob ntawm qhov chaw P sib npaug rau xoom?

(k = 9.10 ⁹ Nm ² .C ^-2 , 1 µC = 10 ^-6 C)

A. 1 cm rau sab xis ntawm q ₁

B. 1 cm rau sab xis ntawm q ₂

C. ½ cm rau sab xis ntawm q ₂

D. ½ cm rau sab laug ntawm q ₁

E. ½ cm rau sab xis ntawm q ₁

Kev Sib Tham

Nws paub tias:

Them 1 (q ₁ ) = -9 µC = -9.10 ^-6 Coulomb

Them 2 (q ₂ ) = 1 µC = 1.10 ^-6 Coulomb

Qhov nrug ntawm q ₁ thiab q ₂ (r ₁₂ ) = 1 cm

k = 9.10 ⁹ Nm2 .C ^{- 2}

Lo lus nug: Qhov chaw P nyob qhov twg kom lub zog hluav taws xob ntawm qhov chaw P sib npaug rau xoom?

Lus teb:

E1 = lub zog hluav taws xob uas tsim los ntawm q1 _{ntawm qhov} chaw P

Lub kev taw qhia ntawm E ₁ yog mus rau q ₁ vim q ₁ yog qhov tsis zoo.

E2 = lub zog hluav taws xob uas tsim los ntawm q2 _{ntawm qhov} chaw P

Qhov kev taw qhia ntawm E ₂ yog deb ntawm q ₂ vim q ₂ yog qhov zoo.

r ₁ = qhov deb ntawm P thiab q ₁ = x + 1

r ₂ = qhov deb ntawm P thiab q ₂ = x

Lub zog hluav taws xob ntawm qhov chaw P yog sib npaug rau xoom:

Siv cov qauv ABC:

Qhov nrug ntawm P thiab q ₂ = x = 0,5 cm.

Taw tes P yog 0,5 cm rau sab xis ntawm q ₂ lossis 0,25 cm rau sab laug ntawm q ₁.

Cov lus teb yog C.

15. Ua tib zoo mloog ob lub nqi uas nyob deb ntawm ib qho hauv qab no!

Yog tias lub zog hluav taws xob ntawm qhov chaw P yog k Q/x ² , ces tus nqi ntawm x yog….

A. 1/3 a

B. 2/3 a

C. ib

D. 3/2 a

E. 2a

Kev Sib Tham

Nws paub tias:

EP = kQ / _x ²

Nug: tus nqi ntawm x

Lus teb:

Siv cov qauv ABC:

Cov lus teb yog lawm yog A.

16. Cov Lus Nug Txog Kev Xeem Hauv Tebchaws rau SMA/MA Physics U-ZC-2013/2014 No. 27

Saib daim duab hauv qab no ntawm ob lub ntsiab lus them nqi!

Qhov chaw P nyob qhov twg kom lub zog hluav taws xob ntawm qhov chaw P sib npaug rau xoom?
(k = 9.10⁹ Nm².C^-2, 1 µC = 10^-6 C)

1. 1 cm rau sab xis ntawm q₁
2. 1 cm rau sab xis ntawm q₂
3. ½ cm rau sab xis ntawm q₂
4. ½ cm rau sab laug ntawm q₁
5. ½ cm rau sab xis ntawm q₁

Kev Sib Tham
Nws paub tias:
Them 1 (q₁) = -9 µC = -9.10^-6 Coulomb
Them 2 (q₂) = 1 µC = 1.10^-6 Coulomb
Qhov deb ntawm q₁ thiab q₂ (r₁₂) = 1 cm
k = 9.10 hli⁹ Nm².C^-2
Nug: Qhov chaw P nyob qhov twg kom lub zog hluav taws xob ntawm qhov chaw P sib npaug rau xoom?
Lus teb:

E₁ = lub zog hluav taws xob tsim los ntawm q₁ ntawm qhov chaw P
Kev Taw Qhia E₁ mus rau q₁ vim q.₁ lub cim tsis zoo
E₂ = lub zog hluav taws xob tsim los ntawm q₂ ntawm qhov chaw P
Kev Taw Qhia E₂ nyob deb ntawm q₂ vim q.₂ lub cim zoo
r₁ = qhov deb ntawm P thiab q₁ = x + 1
r₂ = qhov deb ntawm P thiab q₂ = xwm

Lub zog hluav taws xob 1:
Lub zog hluav taws xob 2:

Lub zog hluav taws xob ntawm qhov chaw P yog sib npaug rau xoom:
a = 8, b = -2, c = -1
Siv cov qauv ABC:

Qhov nrug ntawm P thiab q₂ = x = 0,5 cm.
Point P yog 0,5 cm rau sab xis ntawm q₂ los yog ntawm 0,25 cm rau sab laug ntawm q₁.

Cov lus teb yog C.

17. Cov Lus Nug Txog Kev Xeem Hauv Tebchaws rau SMA/MA Physics U-ZC-2013/2014 No. 27

Xav txog ob lub nqi uas nyob deb ntawm a hauv qab no!
Yog tias lub zog hluav taws xob ntawm qhov chaw P yog k Q / x², ces tus nqi ntawm x yog….

1. 1/3 to
2. 2/3 to
3. a
4. 3/2 to
5. 2a

Kev Sib Tham
Nws paub tias:
E_P = kQ / x²
Nug: tus nqi x
Lus teb:
E₁ = lub zog hluav taws xob ntawm qhov chaw P los ntawm tus nqi -Q
r₁ = qhov deb ntawm lub charge –Q thiab qhov point P = x
E₂ = lub zog hluav taws xob ntawm qhov chaw P los ntawm tus nqi +32Q
r₂ = qhov deb ntawm lub zog them +32Q thiab qhov chaw P = a + x

Siv cov qauv ABC:

Cov lus teb yog lawm yog A.