Ngā wira e hono ana mā te whitiki – ngā raruraru me ngā otinga
1. E toru ngā wira e honoa ana, e ai ki te pikitia i raro nei.
Mena ko R A = 10 cm, ko R B = 4 cm, me R C = 40 cm, ko te ōwehenga o te tere koki o te wira A me te wira C ko …
Mōhiotia:
Te whānui o te wira A (r A ) = 10 cm
Te whānui o te wira B (r B ) = 4 cm
Te whānui o te wira C (r C ) = 40 cm
E hiahiatia ana: te ōwehenga o te tere koki o te wira A me te wira C
Rongoā:
Te tere koki o ngā wira A me C
He nui ake te porowhita o te wira A i te porowhita o te wira C. Ina hurihia te wira C kia kotahi porowhita (360 ° ), i roto i taua wā anō kāore anō te wira A kia huri kia kotahi porowhita (360 ° ). Nō reira, kāore te tere koki o te wira A i te ōrite ki te tere koki o te wira C.
Heoi, e hono ana te wira A me te wira C mā roto i ngā taura, nō reira i roto i te wā kotahi, ko te tawhiti i haerea e te taha o te wira A he rite ki te tawhiti i haerea e te taha o te wira C. Nō reira, ko te tere rārangi o te taha o te wira C (v C ) he rite ki te tere rārangi o te taha o te wira A (v A ).
v A = v C
r A ω A = r C ω C
10 ω A = 40 ω C
ω A / ω C = 40 / 10
ω A / ω C = 4 / 1
[irp]
2. He rite te tuaka hurihuri o ngā wira B me C, ā, he pātata te wira A ki te wira B. Mena ko te pūtoro o te wira A = te pūtoro o te wira C = 30 cm, ko te pūtoro o te wira B = 60 cm, kātahi ka whakatau i te ōwehenga o te tere rārangi i waenga i ngā wira A, B, me C.
Mōhiotia:
Te whānui o te wira A (rA) = 30 henimita = 0.3 mita
Te whānui o te wira B (r B ) = 60 cm = 0.6 mita s
Te whānui o te wira C (r C ) = 30 cm = 0.3 mita s
E hiahiatia ana: te ōwehenga o te tere rārangi i waenga i ngā wira A, B, me C.
Rongoā:
Te tere rārangi o te taha o te wira A :
E hono ana te wira A me te wira B e ai ki te pikitia i raro nei, nō reira, kāore te tere koki o te wira A i te ōrite ki te tere koki o te wira B. Nā te mea he nui ake te porowhita o te wira B i te wira A. I taua wā anō, ina huri te wira A i te porowhita kotahi (360 ° ) , kāore anō te wira B kia huri i te porowhita kotahi (360 ° ). Heoi anō, i taua wā anō, ko te tawhiti i haerea e te taha o te wira A he ōrite ki te tawhiti i haerea e te taha o te wira B. Nō reira, ko te tere rārangi o te taha o te wira A (v° A ) he ōrite ki te tere rārangi o te taha o te wira B (v° B ).
Te tere rārangi o te taha o te wira A:
v A = r A ω A = 0.3 ω A
Te tere rārangi o te taha o te wira B :
Ka piri tahi te wira B me te wira B, nō reira, ka huri tahi te wira B me te wira C. Ina huri te wira B i te porowhita kotahi (360 ° ) i te wā kotahi, ka huri tahi hoki te wira C i te porowhita kotahi (360 ° ). Nā te mea ka huri tahi, ko te tere koki o te wira B (ω B ) he ōrite ki te tere koki o te wira C (ω C ) = ω. Engari kāore te tere rārangi o te wira B (vB) i te ōrite ki te tere rārangi o te wira C ( vC )
Te tere rārangi o te taha o te wira B:
v B = r B ω B = 0.6 ω B = 0.6 ω
Te tere rārangi o te taha o te wira C:
v C = r C ω C = 0.3 ω C = 0.3 ω
He rite te tere rārangi o te taha o te wira A (v A ) ki te tere rārangi o te taha o te wira B ( v B )
v A = v B
0.3 ω A = 0.6 ω
ω A = 0.6 ω / 0.3
ω A = 2 ω
Te tere rārangi o te taha o te wira A (v A ):
v A = 0.3 ω A = 0.3 ( 2 ω) = 0.6 ω
Ko te ōwehenga o te tere rārangi i waenga i ngā wira A, B, me C.
vA: vB : vC
0.6 ω : 0.6 ω : 0.3 ω
0.6:0.6:0.3
6:6:3
2:2: 1
[irp]
