4 ngā tauira o ngā pātai motuhake mō te wera me te kaha o te wera
1. Ko tēhea te mea ka tere ake te wera ina whakamaroketia ngātahi i te rā wera, i te konumohe, i te parahi rānei? Ko te wera motuhake o te konumohe = 900 J/kg o C, ā, ko te wera motuhake o te parahi = 390 J/kg o C.
Kōrero
Ka roa ake te wera o tētahi mea, ka nui ake te wera motuhake. I te taha ke, ka tere ake te wera o tētahi mea, ka iti ake te wera motuhake.
He iti ake te wera motuhake o te parahi i te wera motuhake o te konumohe, nō reira ka tere ake te wera o te parahi.
2. Ka mimitihia e te mea he 2 kg te taumaha o te wera e 100 karori ina huri te pāmahana mai i te 20 ° C ki te 70 ° C. Ko te wera motuhake o te mea ko...
Kōrero
E mōhiotia ana:
Taumaha (m) = 2 kg = 2000 karamu
Wera (Q) = 100 karori
Huringa pāmahana (ΔT ) = 70 ° C – 20 ° C = 50 ° C
I pātaihia: Te wera motuhake o te mea (c)
Whakautu:
c = Q / m ΔT
c = 100 karori / (2000 karamu)(50 ° C)
c = 100 karori / 100.000 karamu o C
c = 10 2 karori / 10 5 karamu o C
c = (10 2 karori)( 10 -5 karamu -1 o C -1 )
c = 10 -3 karori gr -1 o C -1
c = 10 -3 karori / karamu C
Ko te wera motuhake o te mea he 10 -3 karori/karamu o C
3. Ko te wera motuhake o te wai ko 4180 J/kg C o . Ko te kaha wera o te 2 kg o te wai ko…..
Kōrero
E mōhiotia ana:
Te wera motuhake o te wai (c) = 4180 J/kg C o
Taumaha (m) = 2 kg
I pātaihia: Te kaha wera (C)
Whakautu:
C = mc
C = (2 kg)(4180 J/kg C o )
C = (2)(4180 J/C o )
C = 8360 J/C o
4. Ko te wera motuhake o te konumohe he 900 J/kg C o . Ko te kaha wera o te 2 karamu o te konumohe he…..
Kōrero
E mōhiotia ana:
Te wera motuhake o te konumohe (c) = 900 J/kg C o = 9 x 102 J /kg C o
Taumaha (m) = 2 karamu = 2/1000 kg = 2/10 3 kg = 2 x 10 -3 kg
I pātaihia: Te kaha wera (C)
Whakautu:
C = mc
C = (2 x 10 -3 kg)( 9 x 10 2 J/kg C o )
C = 18 x 10 -3 x 10 2 J/C o
C = 18 x 10 -1 J/C o
C = 1,8 J/C o
