Te ture a Coulomb – ngā raruraru me ngā otinga

1. E rua ngā utunga pūwāhi, Q_A = +8 μC me te Q_B = -5 μC, e wehea ana e te tawhiti r = 10 cm. He aha te rahi o te te kaha hiko. Ko te pūmau k = 8.988 x 10⁹ Nm²C^-2 = 9x10⁹ Nm²C^-2.

Mōhiotia:

Utu A (q _A ) = +8 μC = +8 x 10 ^-6 C

Utu B (q _B ) = -5 μC = -5 x 10 ^-6 C

k = 9 x 10 ⁹ Nm ² C ⁻²

Ko te tawhiti i waenganui i ngā utu A me B (r _AB ) = 10 cm = 0.1 m

E hiahiatia ana : Te rahi o te kaha hiko

Rongoā:

Te tauira o te ture a Coulomb :

Te rahi o te kaha hiko:

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2. E rua ngā matūriki kua utua, e whakaaturia ana i te pikitia i raro nei. Ko Q _P = +10 μC me Q _q = +20 μC e wehea ana e te tawhiti r = 10 cm. He aha te rahi o te kaha hiko-pūmau?

Mōhiotia:

Utu P (Q _P ) = +10 μC = +10 x 10 ^-6 C

Utu Q (Q _Q ) = +20 μC = +20 x 10 ^-6 C

k = 9 x 10 ⁹ Nm ² C ⁻²

Ko te tawhiti i waenganui i ngā utu P me Q (r _PQ ) = 12 cm = 0.12 m = 12 x 10 ^-2 m

E hiahiatia ana: Te rahi o te kaha hiko

Rongoā:

[irp]

3. E toru ngā matūriki kua whakarārangihia kia rite ki te pikitia i raro nei. Utu A = -5 μC, utu B = +10 μC me utu C = -12 μC. Tātaihia te kaha hiko pūmau ki runga i te matūriki B nā ngā utu e rua e toe ana.

Mōhiotia:

Utu A (q _A ) = -5 μC = -5 x 10 ^-6 C

Utu B (q _B ) = +10 μC = +10 x 10 ^-6 C

Utu C (q _C ) = -12 μC = -12 x 10 ^-6 C

k = 9 x 10 ⁹ Nm ² C ⁻²

Ko te tawhiti i waenganui i ngā matūriki A me B (r _AB ) = 6 cm = 0.06 m = 6 x 10 ^-2 m

Ko te tawhiti i waenganui i ngā matūriki B me C (r _BC ) = 4 cm = 0.04 m = 4 x 10 ^-2 m

E hiahiatia ana: Te rahi me te ahunga o te kaha hikohiko kupenga i runga i te matūriki B

Rongoā:

Ko te kaha kupenga i runga i te matūriki B ko te tapeke whārite o te kaha F _BA i pā ki te matūriki B e te matūriki A me te kaha F _BC i pā ki te matūriki B e te matūriki C.

Ko te kaha F _BA i pā ki te matūriki B e te matūriki A:

 

Ko te ahunga o te kaha hikohiko e tohu ana ki te matūriki A (e tohu ana ki te maui).

Ko te kaha F _BC i pā ki te matūriki B e te matūriki A:

 

Ko te ahunga o te kaha hikohiko e tohu ana ki te matūriki C (tohu ki te taha matau).

Ko te kaha hiko pūmau kupenga i runga i te matūriki B :

F _B = F _AB – F _BC = 675 N – 125 N = 550 Ngā Newton.

Ko te ahunga o te kaha hiko pūmau i runga i te matūriki B e tohu ana ki te matūriki C (e tohu ana ki te taha matau).

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4. Kua wehea a +Q ₁ = 10 μC, +Q ₂ = 50 μC me Q ₃ e ai ki te pikitia i raro nei. He aha te utu hiko pūmau i runga i te matūriki 3 mēnā he kore te kaha hiko pūmau kupenga i runga i te matūriki 2.

Mōhiotia:

Utu 1 (q ₁ ) = +10 μC = +10 x 10 ^-6 C

Utu 2 (q ₂ ) = +50 μC = +50 x 10 ^-6 C

Ko te tawhiti i waenganui i ngā utu 1 me te 2 (r ₁₂ ) = 2 cm = 0.02 m = 2 x 10 ^-2 m

Ko te tawhiti i waenganui i te utu 2 me te utu 3 (r ₂₃ ) = 6 cm = 0.06 m = 6 x 10 ^-2 m

Ko te kaha hiko pūmau kupenga i runga i te matūriki 2 (F ₂ ) = 0

E hiahiatia ana : utu 3 (q ₃ )

Rongoā:

Ko te kaha kupenga i runga i te matūriki 2 ko te tapeke whārite o te kaha F ₂₁ i pā ki te matūriki 2 e te matūriki 1 me te kaha F ₂₃ i pā ki te matūriki 2 e te matūriki 3.

Ko te kaha F ₂₁ i pā ki te matūriki 2 e te matūriki 1:

Ko te ahunga o te kaha hikohiko e tohu ana ki te matūriki 3 (tohu ki te taha matau).

Te kaha F₂₃ i pāngia e te matūriki 3 ki te matūriki 2: 

Ko te ahunga o te kaha hikohiko e tohu ana ki te matūriki 1 (tohu ki te maui).

Ko te kaha hiko pūmau kupenga i runga i te matūriki 2 = 0: