Ngā tauira pātai me ngā tātai mō te pūngao hiko me te mana
Pūngao me te Mana Hiko
1. Ko te utu hiko mō ia kWh he Rp. 400. I roto i tētahi whare, e 4 hāora te roa o te mahi a tētahi pouaka whakaata 100 Watt i te rā, ā, e rua ngā rama 20 Watts i ia rama e whakamahia ana mō ngā hāora 10 i te rā. Ko te utu whakamahi hiko mō ia marama (30 rā) ko….
A. Rp. 4.800,-
B. Rp. 9.600,-
C. Rp. 19.200,-
D. Rp. 21.120,-
Kōrero
E mōhiotia ana:
Ko te utu hiko he Rp. 400/kWh
Mana pouaka whakaata = 1 x 100 Watt = 100 Watt me te wā whakamahi pouaka whakaata = 4 hāora x 30 = 120 hāora
Mana rama = 2 x 20 Watt = 40 Watt me te wā whakamahinga rama = 10 hāora x 30 = 300 hāora
I pātaihia: Te utu mō te whakamahinga hiko ia marama
Whakautu:
Pūngao hiko = mana hiko x wā whakamahinga
Pūngao hiko pouaka whakaata = 100 Watt x 120 hāora = 12.000 Watt hāora
Pūngao rama = 40 Watt x 300 hāora = 12.000 Watt hāora
Pūngao katoa = 12.000 hāora Watt + 12.000 hāora Watt = 24.000 hāora Watt = 24 kiro Watt hāora = 24 kiro Watt hāora = 24 kWh
Te utu mō te whakamahinga hiko i ia marama = (24 kWh)(Rp. 400/kWh) = (24)(Rp. 400) = Rp. 9.600,-
Ko te whakautu tika ko B.
2. E rua ngā rama, ko ia rama he 24 Watt / 12 Volt te tohu, ka honoa whakarara, kātahi ka honoa raupapa ki tētahi ātete 2 Ohm. Kātahi ka honoa tēnei ara iahiko ki tētahi pūtake ngaohiko kia mura ai ngā rama e rua i te 25% noa iho o tō rāua kanapa mōrahi. Mēnā ka pakaru ohorere tētahi rama, ka mura te rama kē atu me te hiko….
A. 12 Wāti
B. 7,5 Wāti
C. 6 Wāti
D. 3 Wāti
Kōrero
Tātai mana:
P = VI
I = PV
ranei
P = VI —–> I = V / R
P = V (V / R)
P = V2 / R
R = V2 / P
ranei
P = VI —–> V = IR
P = (IR) I
P = I2 R
I2 = P / R
Whakaahuatanga: P = mana hiko, V = ngaohiko hiko, I = iahiko hiko, R = ātete rama
Tātaihia te ātete ara iahiko:
E rua ngā rama kua tohua ki te 24 Watt / 12 Volt, ko te tikanga ka kā ia rama i te mana mōrahi o te 24 Watts ina honoa ki te ngaohiko o te 12 Volts.
Ka tatauhia te ātete o ia rama mā te whakamahi i te tātai mana:
R = V2 / P = 122 / 24 = 144 / 24 = 6 Ōhm
E honoa ana ngā rama e rua i te taha whakarara, nō reira ko te ātete ōrite ko:
1 / R12 = 1/R1 + 1/R2 = 1/6 + 1/6 = 2/6
R12 = 6/2 = 3 Ōhm
Ka honoa ngā rama e rua i roto i te raupapa mā te whakamahi i tētahi ātete 2 Ohm, nō reira ko te ātete ōrite ko:
R = 3 Ōhm + 2 Ōhm = 5 Ōhm
Nō reira, ko te ātete ara iahiko = R = 5 Ohm.
Tātaihia te iahiko e rere ana i roto i te ara iahiko:
Mena kei te kā ngā rama e rua, ā, ko te taumata kanapa o te 25%, kātahi ka kā ngā rama e rua, ā, ko te mana o aua rama he 25/100 x 24 Watts = 1/4 x 24 = 24/4 = 6 Watts.
Ka tatauhia te iahiko e rere ana i roto i te rama mā te whakamahi i te tātai mana:
I2 = P / R = 6 Watts / 6 Ohms = 1 Ampere
Ko te iahiko e rere ana i roto i ia rama he 1 Ampere. Ka honoa ngā rama e rua i te taha whakarara, nō reira, e ai ki te ture tuatahi a Kirchhoff, ko te iahiko katoa e rere ana i roto i ngā rama e rua he 2 Ampere. Ka honoa ngā rama e rua i te taha raupapa me te ātete 2 Ohm, nō reira, ko te iahiko e rere ana i roto i te ātete 2 Ohm he 2 Ampere anō hoki.
Nō reira, ko te iahiko e rere ana i roto i te ara iahiko = I = 2 Amperes.
Tātaihia te ngaohiko o te pūtake emf:
Ko te ngaohiko hiko ko:
V = IR = (2 Ampere)(5 Ohm) = 10 Volts
Koinei te ngaohiko o te pūtake EMF kāore tōna uara e rerekē i mua i te pakaru o tētahi o ngā rama, i muri rānei i te pakaru o tētahi o ngā rama.
Tātaihia te ātete o te ara iahiko i muri i te whatinga o tētahi o ngā rama:
Ki te pakaru tētahi o ngā rama, ka honoa raupapatia te rama kē atu e kā tonu ana ki tētahi ātete 2 Ohm. Nō reira, ka huri te ātete o te ara iahiko ki:
R = 6 Ōhm + 2 Ōhm = 8 Ōhm
Tātaihia te iahiko e rere ana i roto i te ara iahiko i muri i te whatinga o tētahi o ngā rama:
Ko te iahiko e rere ana i roto i te ara iahiko ko:
I = V / R = 10 Volts / 8 Ohms = 1,25 Amps
Ka honoa raupapa te rama me te ātete kia rite ai te iahiko e rere ana i roto i te ara iahiko = te iahiko e rere ana i roto i te rama = te iahiko e rere ana i roto i te ātete.
Tātaihia te mana o te rama:
I muri i te whatinga o tētahi o ngā rama, ka tiaho ngā rama kē atu me te mana o:
P = VI = (10 Volt)(1,25 Ampere) = 12,5 Watt
Te nekehanga o te irahiko
3. E mōhiotia ana ko te papatipu o te irahiko he 9,1 x 10-31 kg me te utu irahiko 1,6 x 10-19 C. Te rerekētanga pūmanawa e hiahiatia ana hei whakatere i tētahi irahiko mai i te tere o te 1 x 105 ka huri te m/s ki te 3 x 105 ko te m/s…
A. 28,4375 mV
B. 56,875 mV
C. 113,75 mV
D. 227,5 mV
Kōrero
E mōhiotia ana:
Papatipu irahiko (m) = 9,1 x 10-31 kg
Utu irahiko (q) = 1,6 x 10-19 C
Te tere tīmatanga (vo) = 1 x 105 m/s —> vo2 = 1x1010 m2/s2
Te tere whakamutunga (vt) = 3 x 105 m/s —> vt2 = 9 x 1010 mita2/s2
I pātaihia: Ko te rerekētanga pūmanawa (V) e hiahiatia ana hei whakatere i te irahiko
Whakautu:
Te huringa o te pūngao pūmanawa hiko = q V = (1,6 x 10-19 C) V
Huringa o te pūngao nekeneke = EKt – EKo = 1/2 m (vt2 -vo2) = 1/2 (9,1 x 10-31 kg)(9 x 1010 m2/s2 - 1 x 1010 m2/s2) = (4,55 x 10-31 kg)(8 x 1010 m2/s2) = 36,4 x 10-21 kg m2/s2
He pūngao pumau tonu, nō reira ka huri te pūngao pūmanawa hiko hei pūngao nekeneke:
I hinga a EPL = kua puta a EK
(1,6x10-19) V = 36,4 x 10-21
V = 36,4 x 10-21 / 1,6 x 10-19
V = 22,75 x 10-2 wae ngaohiko
V = 227,5 x 10-3 wae ngaohiko
V = 227,5 milliVolts
Ko te whakautu tika ko D.
4. Ngā Pātai mō te Whakataetae Pūtaiao ā-Motu 2011 mō ngā Kura Tuarua i te Taumata Rohe/Tāone Nama 56
I roto i tētahi taiwhanga, ka tukuna he hihi o ngā irahiko ki te raki. Mai i runga, ka kitea te piko o te hihi ki te maui. Kātahi ka tukuna he hihi o ngā irahiko ki te tonga. Mai i runga, ka kitea te piko o te hihi ki te maui. Ko te tikanga tēnei he…
A. te papa hiko e tohu ana ki te hauauru
B. te papa hiko e tohu ana ki te rawhiti
C. te papa aukume e anga whakarunga ana
D. te papa aukume e anga ana ki raro
Kōrero
He hiko te utu o ngā irahiko, ā, ka taea te neke e ngā kaha hiko, aukume rānei ina noho ana i roto i te papa hiko, i te papa aukume rānei. Ko te rerekētanga, ka taea e ngā kaha hiko te neke i ngā irahiko ina okioki, ina neke hoki, engari ko ngā kaha aukume anake ka taea te neke i ngā irahiko ina neke ana.
Ko tētahi atu rerekētanga ko te kaha hiko kei te ahunga kotahi ki te papa hiko, ko te kaha aukume ia he poutū ki te papa aukume. Nō reira, ki te nekehia he irahiko e te kaha hiko, ka rite te ahunga o tōna nekehanga ki te ahunga o te papa hiko. I tetahi atu taha, ki te nekehia he irahiko e te kaha aukume, ka rite te ahunga o tōna nekehanga ki te ahunga o te kaha aukume, e poutū ana ki te ahunga o te papa aukume.
I runga i te pātai i runga ake nei, te āhua nei ina pupuhihia he irahiko ki te raki, ka piko ki te taha maui (ki te hauauru), ā, ina pupuhihia ki te tonga, ka piko ki te taha maui (ki te rawhiti). Mēnā ka pikohia he irahiko e te kaha hiko, ko te ahunga o te kaha hiko, he rite tonu ki te ahunga o te mara hiko, kei te huri tonu. Me pumau te ahunga o te mara hiko. Nō reira, kāore te irahiko e pikohia e te kaha hiko.
Ka taea te whakatau ko te kaha aukume ka whakapiko i ngā irahiko. Hei whakatau i te ahunga o te kaha aukume (te ahunga e whakapikohia ana ngā irahiko), te ahunga o te papa aukume, me te ahunga e pupuhihia ana ngā irahiko, whakamahia te ture ringa-matau.
Whakamahia te ture ringa-matau e whakamāramahia ana i raro nei. Totorohia tō ringa matau, whakatikahia tō koromatua, ā, katia ō maihao e whā. Tūhia tō koromatua kia anga ki te raki (te ahunga o te nekehanga irahiko) ā, e anga ana ō maihao e whā ki te hauauru (ko te ahunga o te kaha aukume = te ahunga o te piko o te irahiko), kātahi ka anga te tuara o tō ringa matau ki raro (te ahunga o te papa aukume). I tētahi atu taha, tūhia tō koromatua kia anga ki te tonga (te ahunga o te nekehanga irahiko) ā, e anga ana ō maihao e whā ki te rawhiti (ko te ahunga o te kaha aukume = te ahunga o te piko o te irahiko), kātahi ka anga te tuara o tō ringa matau ki raro (te ahunga o te papa aukume). Ka taea te whakatau ko te irahiko kei roto i te papa aukume e anga ana ki raro.
Ko te whakautu tika ko D.
Pūtake pātai:
Ngā Pātai OSN mō te Ahupūngao o te Kura Tuarua
