Mienzaniso mina yeMibvunzo yeKusimba Kwenzwi
1. Mapoinzi A naB ari 4 m uye 9 m kubva panobva ruzha, zvichiteerana. Kana I A naI B dziri simba reruzha pamapoinzi A naB, zvichiteerana , saka I A : I B ndiye…
A. 3: 2
B. 4: 9
C. 9 : 4
D. 16: 81
Chikamu 81: 16
Kukurukurirana
Zvinozivikanwa kuti:
Kureba kwenzvimbo A kubva panobva ruzha (r A ) = mamita 4
Kureba kwenzvimbo B kubva panobva ruzha (r B ) = mamita mazana mana
Kusimba kweruzha panzvimbo A = I A
Kusimba kweruzha panzvimbo B = I B
Akabvunzwa: Ini : Ini B
Mhinduro:
Fomura yehukama huripo pakati pekusimba uye daro:
Mhinduro chaiyo ndiE.
2. Ruzha rwemuchina wekusona kana uchishanda i10-9 Wm-2Kuti ruzha ruve nesimba re10-12 Wm-2, ipapo huwandu hwekurira kwemuchina wekusona gumi wakafanana uri kushanda ndewekuti…..
A. 400 dB
B. 300 dB
C. 40 dB
D. 30 dB
E. 20 dB
Kukurukurirana
Zvinozivikanwa kuti:
I = 10 -9 W/m 2
I o = 10 -12 W/m 2
x = 10
Akabvunzwa: Muchina wekusona weTI 10?
Mhinduro:
Michina yeTI 10 = TI muchina 1 + 10 log x
TI = 30 + 10 log 10
TI = 30 + 10 log 10 1
TI = 30 + (1)(10)(log 10)
TI = 30 + 10
TI = 40 dB
Mhinduro chaiyo ndiC.
3. Kurira kweruzha rwenyuchi imwe chete i10 dB. Kana ruzha rweruzha rwenyuchi imwe neimwe rwuchinzi rwakafanana uye chiyero chekunzwa kwevanhu chiri 10 −12 Wm −2 , saka kurira kweruzha rwenyuchi chiuru…
A. 10 −8 Wm −2
B. 10 −7 Wm −2
C. 10 −6 Wm −2
D. 10 −5 Wm −2
E. 10 −4 Wm −2
Kukurukurirana
Zvinozivikanwa kuti:
TI = 10 dB
I o = 10 -12 W/m 2
x = 1000
Akabvunzwa: Nyuchi dzeTI 1000?
Mhinduro:
4. Ruzha rwehwamanda yemudhudhudhu kana rwuridzwa rwunoburitsa simba re40 dB, ukuwo ruzha rwehwamanda yemotokari kana rwuridzwa rwunoburitsa simba re60 dB (Io = 10 -12 W m -2 ). Kana hwamanda dzemudhudhudhu zana nehwamanda dzemotokari gumi dzichiridzwa panguva imwe chete, saka chiyero chesimba remudhudhudhu kumotokari ndeche ....
A. 5: 6
B. 6: 7
C. 7 : 8
D. 8: 9
Chikamu 9: 10
Kukurukurirana
Zvinozivikanwa kuti:
Kusimba kwenzwi rebhoni yemudhudhudhu (TI) = 40 dB
Huremu hwehuronyo hwemotokari (TI) = 60 dB
Avhareji yesimba shoma rinogona kunzwiwa nevanhu (Io ) = 10 -12 W m -2
Mubvunzo: Chii chinonzi TI ratio yemidhudhudhu zana neTI yemota gumi?
Mhinduro:
Kuenzaniswa kwemidhudhudhu yeTI 100 nemota dzeTI 10 ndekwekuti:
60: 70
6: 7
Mhinduro chaiyo ndeiyi B.
Kwakabva mubvunzo:
Mibvunzo yeNational Examination Physics yeChikoro Chesekondari/Chikoro Chepamusoro Chebasa
