Misalan Tambayoyi 6 na Dokar Archimedes
1. Wane girman dutse ne aka sanya a cikin ruwan teku idan nauyin ruwan teku da dutsen ya kone ya kai Newtons 2? Yawan ruwan teku = 1025 kg/m23.
Tattaunawa
Amsa:
Dokar Archimedes Ya ce nauyin ruwan da aka zubar (ruwan da ƙarfe ya kora) daidai yake da babban ƙarfin tururi wanda ake yi da ruwa a kan ƙarfe.
Yawan ruwan da aka kora = girman dutsen da aka nutsar a cikin ruwan teku = 199,1 cm 3.
2. Kwantenan da ke cike da ruwa. Guda ɗaya na ƙarfe 2 cm3 a nutsar da shi a cikin akwati don ruwan ya zube. Nawa ne nauyin ruwan da ke zubewa?
Tattaunawa
3. Nauyin abu a cikin iska shine kilogiram 15, nauyin abu a cikin ruwa shine kilogiram 13,7. Shin an yi abin ne da zinare tsantsa?
Tattaunawa
An san cewa:
m = 15 kg
m' = 13,7 kg
An tambaya: shin an yi abin ne da zinare tsantsa?
Amsa:
Nauyi na musamman Zinariya tsantsa = 19,3 ko kuma yawan zinare tsantsa = 19300 kg/m23Idan yawan abu iri ɗaya ne da yawan zinariya tsantsa, to an yi abin ne da zinariya tsantsa.
Menene yawan abu? ?
Ƙarfin hayaniya (F)A) yayi daidai da nauyin abu a cikin iska (w) an rage nauyin abu a cikin ruwa (w').
Shigar da ƙimar taro na abu a cikin iska da ƙimar taro na abu a cikin ruwa:
Rabon yawan abu da yawan ruwa (/) = takamaiman nauyin abu. Don haka takamaiman nauyin abu = 11,3.
Yawan abu = takamaiman nauyi da aka ninka da yawan ruwa = (11,3)(1000 kg/m3) = 11.300 kg/m23.
Nauyin zinare tsantsa shine 19,3 kuma yawan zinare shine 19.300 kg/m23 saboda haka ba a yi abin da aka yi da zinariya tsantsa ba.
4. Wani jirgin ceto yana ƙoƙarin ɗaga wani akwati mai nauyin kilogiram 4500 wanda ya faɗa cikin teku. Kwantena yana da tsawon mita 2, faɗin mita 1,5, da tsayin mita 1. Yawan ruwan teku a wannan lokacin shine kilogiram 1025/m3 kuma saurin gudu saboda nauyi shine 10 m/s2 . Saboda haka, mafi ƙarancin ƙarfin da ake buƙata don ɗaga abin daga ƙasan teku zuwa saman shine…
Tattaunawa
An sani:
Nauyin akwati (m) = 4500 kg
Ƙarar akwatin (V) = 2 mx 1,5 mx 1 m = 3 m3
Yawan ruwan teku ( ρ) = 1025 kg/ m3
Saurin gudu saboda nauyi (g) = 10 m/s 2
Tambaya: Menene ƙaramin ƙarfin da ake buƙata don ɗaga abu daga ƙasan teku zuwa saman ruwa?
Amsa:
Nauyin abu a cikin iska = mg = (4500 kg)(10 m/s 2 ) = 45000 N
Don ɗaga abu a ƙasa, mafi ƙarancin ƙarfin shine N45000.
Girman ƙarfin tururin iska:
F A = ρ F g V = ( 1025) (10) (3) = 30750 N
Nauyin abu a cikin ruwan teku = 45000 N – 30750 N = 14250 N
Don ɗaga abu a teku, mafi ƙarancin ƙarfin shine 14250 N.
5. Wani abu yana shawagi a cikin ruwa wanda yawansa shine 800 kg/m3Idan ¼ na abin bai nutse cikin ruwan ba, to yawan abin...
A. 600 kg/m3
B. 900 kg/m3
C. 1000 kg/m3
D. 1200 kg/m3
E. 1300 kg/m3
Tattaunawa:
An san cewa:
Yawan yawa ruwa = 800 kg/m23
Girman abu wanda ba a nutsar da shi cikin ruwa ba = ¼
Girman abu da aka nutsar a cikin ruwa = ¾
Jimlar girman abin = 1
An tambaya :
Yawan yawa abu?
Jawab :
Tsarin dangantakar da ke tsakanin yawa An tattauna abubuwa, yawan ruwa da sassan abubuwan da aka nutsar kuma ba a nutsar da su cikin ruwa ba a cikin labarin me yasa abubuwa masu ƙarfi suke iyo? :
Amsar da ta dace ita ce A.
6. Nauyin abu a cikin iska shine N5. Idan an auna abu a cikin ruwa (yawan ruwa = 1000 kg/m23) nauyin ya zama N3,2. Idan hanzarin da aka samu saboda nauyi g = 10 m/s2 to yawan abin shine...
A. 800 kg/m3
B. 1000 kg/m3
C. 1500 kg/m3
D. 2500 kg/m3
E. 2780 kg/m3
Tattaunawa:
An san cewa:
Nauyin abu a cikin iska = Nauyin abu (w) = 5 Newtons
Nauyin abu a cikin ruwa = 3,2 Newtons
Yawan yawa ruwa = 1000 kg/m23
Haɓaka Nauyi = 10m/s2
Nauyin abu: w = mg —> m = w : g = 5 N : 10 m/s2 = 0,5kg
An tambaya:
Yawan yawa abu?
Amsa:
Nauyin abu a cikin ruwa ya ƙanƙanta saboda ƙarfin hawan dutse.
Buɗewa = Nauyin abu a cikin iska - Nauyin abu a cikin ruwa
Buɗewa = 5 Newtons – 3,2 Newtons = 1,8 Newtons
Yawan Abu :
Yawan = Nauyi: Girma = 0,5 kg: 0,00018 m3 = 2780 kg/m3
Amsar da ta dace ita ce E.
Tambayoyin dokar Archimedes
1. Wane girman dutse ne ake sanyawa a cikin ruwan idan nauyin ruwan da dutsen ya kone ya kai Newtons 5? Yawan ruwa = 1000 kg/m23 (501 cm3)
2. Kwantenan da ke cike da fetur. Katako mai tsawon 1,2 dm3 an nutsar da shi a cikin akwati har sai da wasu daga cikin man fetur suka zube. Nawa ne nauyin man fetur ɗin da ya zube? (gram 816)
3. Nauyin ƙarfe a cikin iska shine kilogiram 13 kuma nauyin ƙarfe a cikin ruwa shine kilogiram 12,3. Shin ƙarfen an yi shi ne da zinari tsantsa? (A'a, domin takamaiman nauyin ƙarfen = 18,6. Takamaiman nauyin zinariya = 19,3)
