Lipotso tsa Mohlala oa Maqhubu a Molumo

Mehlala e 16 ea lipotso tsa Maqhubu a Molumo

1. Moshebelli peisong ea likoloi o utloa melumo e fapaneng (molumo oa likoloi) ha likoloi li ntse li atamela 'me li khutlela morao. Koloi e tloaelehileng ea peiso e hlahisa molumo oa 800 Hz. Haeba lebelo la molumo moeeng e le 340 m/s,^-1 'me lebelo la koloi ke 20 ms^-1, ebe maqhubu a utlwahalang ha koloi e atamela ke….
A. 805 Hz

B. 810 Hz

C. 815 Hz

D. 850 Hz

E. 875 Hz

Puisano

Hoa tsebahala hore:

v _s = -20 m/s (e mpe hobane koloi e suthela hole le momameli)

v _p = 0 (momameli o khutsitse hobane o shebelletse)

f = 800 hz

v = 340 m/s

Botsitswe: O utlwa modumo o kae?

Karabo:

Karabo e nepahetseng ke D.

2. Motho o tsamaya ka lebelo la 10 m/s ⁻¹ ho ya mohloding wa modumo o sa sisinyeheng o nang le maqhubu a 680 Hz. Kamora ho fihla mohloding wa modumo, motho o tsamaya hole le mohloding wa modumo ka lebelo le le leng. Haeba lebelo la mohloding wa modumo moyeng e le 340 m/s ⁻¹ , jwale karolelano ya maqhubu a mabedi a utlwiwang ha o fallela mohloding ho ya ha o tloha mohloding ke...

A. 33/34

B. 33/35

C. 34/35

D. 35/33

E. 35/34

Puisano

Hoa tsebahala hore:

v = 340 m/s

v _p = 10 m/s

v _s = 0

f = 680 hz

Potso: Karolelano ea maqhubu a molumo ke efe ha momameli a atamela mohloli ha momameli a suthela hole le mohloli?

Karabo:

Momameli o tloha mohloling:

Papiso ea maqhubu a utluoang:

700: 660 = 70: 66 = 35: 33

Karabo e nepahetseng ke D.

3. Terene e tsamaeang ka lebelo la 72 km/h e atamela sebaka seo terene e tšelang ho sona ha e ntse e letsa mololi ka maqhubu a 1600 Hz. Haeba lebelo la molumo moeeng e le 340 ms-1, joale maqhubu a mololi a utluoang ke molebeli oa terene ke ….

A. 3600 Hz

B. 3400 Hz

C. 1800 Hz

D. 1700Hz

E. 1400Hz

Puisano

Hoa tsebahala hore:

Lebelo la mohlodi wa modumo (vs ₎ = 72 km/h = 20 m/s (ha ho bapiswa le sebaka se tsamaisang modumo)

Maqhubu a mohlodi wa modumo (f) = 1600 Hz

Lebelo la molumo moeeng (v) = 340 m/s

Lebelo la momameli (v _p ) = 0 (lefela hobane momameli ha a sisinyehe)

E botsitsweng: maqhubu a modumo a utluwang ke molebedi (f')?

Karabo:

Karabo e nepahetseng ke D.

4. Teraka ea mollo e tsamaea ka lebelo la 20 ms ^-1 ha e ntse e letsa siren ea eona ka maqhubu a 400 Hz (lebelo la molumo moeeng ke 300 ms ^-1 ). Haeba teraka ea mollo e tloha ho motho ea emeng ka thoko ho tsela, motho eo o tla utloa siren ka maqhubu a….

A. 375 Hz

B. 575 Hz

C. 600 Hz

D. 620 Hz

E. 725 Hz

Puisano

Hoa tsebahala hore:

v _s = 20 m/s (e ntle hobane koloi e suthela hole le momameli)

v _p = 0 (momameli ea khutsitseng ka thoko ho tsela)

f = 400 hz

v = 300 m/s

Botsitswe: O utlwa modumo o kae?

Karabo:

Karabo e nepahetseng ke A.

5. Sebuela-hōle se tsoang toreng ea temoso se ntša molumo ka maqhubu a 670 Hz. Koloi e atamela toreng ka lebelo la 90 km/h. Haeba lebelo la molumo moeeng ka nako eo e le 335 m/s, joale maqhubu a molumo o tsoang sebuela-hōle o utluoang ke mokhanni oa koloi ke…

A. 900 Hz

B. 840 Hz

C. 800 Hz

D. 750 Hz

E. 720 Hz

Puisano

Hoa tsebahala hore:

f = 670 hz

v _s = 0 (tora e phomotseng)

v _p = 90 km/h = 25 m/s (e ntle hobane momameli o atamela mohloli oa molumo)

v = 335 m/s

Potso: Molumo o utluoang ke mokhanni (f') o le makhetlo a makae?

Karabo:

Karabo e nepahetseng ke E.

6. Dini o ne a le tereneng e emeng A. Terene e 'ngoe (B) e ntse e leba A ka lebelo la 2 ms^-1 ha o ntse o letsa mololi ka maqhubu a 676 Hz. Haeba lebelo la modumo moyeng e le 340 ms^-1, ebe kgafetsa ya molodi wa terene B oo Dini a o utlwileng e ne e le….
A. 680 Hz

B. 676 Hz

C. 660 Hz

D. 656 Hz

E. 640 Hz

Puisano

Hoa tsebahala hore:

v _s = -2 m/s (terene e mpe B e atamela Dini mme e terene A

v _p = 0 (Dini o ka tereneng e emeng)

f = 676 hz

v = 340 m/s

Botsitswe: Dini o utlwile maqhubu a terene ya B ka tsela efe?

Karabo:

Karabo e nepahetseng ke A.

7. Sebapali sa bolo ea maoto se matha ka lebelo la v _p ho ea ho moahloli ea sa emeng ha se ntse se letsa mololi ka makhetlo a f _s . Haeba lebelo la moea sebakeng seo e le v, joale makhetlo ao sebapali se a utloang a etsoa joalo ka….

Puisano

Hoa tsebahala hore :

v _s = 0 (moahloli o khutsitse)

v _p = v _p (e ntle hobane e atamela mohloli oa molumo)

f = _fs

v = v

Potso : Foromo ea makhetlo a utluoang ke libapali tsa bolo ea maoto ke efe?

Karabo :

Karabo e nepahetseng ke A.

8. Ambulense A e tsamaya ka lebelo la 0,25 v ka morao ho sedan B e tsamayang ka lebelo la 0,2 v ka lehlakoreng le le leng le A. Ka nako eo, ambulense A e letsa siren ya yona ho 1.000 Hz. Haeba lebelo la modumo e le v, maqhubu a utluwang ke mokhanni wa sedan B ke…

A. 1.500 Hz

B. 1.250 Hz

C. 1.111 Hz

D. 1.067 Hz

E. 1.000 Hz

Puisano

Hoa tsebahala hore :

Maqhubu a mohlodi wa modumo (f) = 1.000 Hz

Lebelo la mohlodi wa modumo (vs _s ) = -0,25 v (ha ho bapiswa le modumo o tsamaisang modumo)

Lebelo la molumo (v) = v

Lebelo la momameli (v _p ) = -0,2 v (ha ho bapisoa le seaplane se tsamaisang molumo)

Ho batloa : Khafetsa ha molumo o utluoa ke momameli (f')

Karabo :

Foromo ea phello ea Doppler:

Karabo e nepahetseng ke D.

9. Mohloli oa molumo o nang le maqhubu a 640 Hz o leba ho moshebelli ka lebelo la 20 m/s. Haeba lebelo la molumo moeeng e le 340 m/s 'me moshebelli a tloha mohloling oa molumo ka lebelo la 10 m/s, joale maqhubu a molumo o utluoang ke moshebelli ke…

A. 600 Hz

B. 660 Hz

C. 900 Hz

D. 980 Hz

E. 1300 Hz

Puisano

Hoa tsebahala hore :

Maqhubu a mohlodi wa modumo (f) = 640 Hz

Lebelo la mohlodi wa modumo (vs _s ) = -20 m/s (ha ho bapiswa le moya e le sesebediswa se tsamaisang modumo)

Lebelo la molumo (v) = 340 m/s (ha le bapisoa le moea e le sesebelisoa sa phetisetso ea molumo)

Lebelo la momameli (v _p ) = -10 m/s (ha ho bapisoa le moea e le sesebelisoa se tsamaisang molumo)

Ho batloa : Khafetsa ha molumo o utluoa ke momameli (f')

Karabo :

Karabo e nepahetseng ke B.

10. Mohloli oa molumo o tsamaea ka lebelo la 60 m/s o siea moshebelli ka mor'a oona a tsamaea ka lehlakoreng le le leng le mohloli oa molumo ka lebelo la 10 m/s. Haeba lebelo la molumo moeeng e le 340 m/s 'me maqhubu a mohloli oa molumo e le 800 Hz, joale maqhubu a molumo o utluoang ke moshebelli ke…

A. 700 Hz

B. 800 Hz

C. 940 Hz

D. 960 Hz

E. 1.120 Hz

Puisano

Hoa tsebahala hore :

Maqhubu a mohlodi wa modumo (f) = 800 Hz

Lebelo la mohlodi wa modumo (vs _s ) = 60 m/s (ha ho bapiswa le moya e le sesebediswa se tsamaisang modumo)

Lebelo la molumo (v) = 340 m/s (ha le bapisoa le moea e le sesebelisoa sa phetisetso ea molumo)

Lebelo la momameli (v _p ) = 10 m/s (ha ho bapisoa le moea e le sesebelisoa se tsamaisang molumo)

Ho batloa : Khafetsa ha molumo o utluoa ke momameli (f')

Karabo :

Karabo e nepahetseng ke A.

Matla a Molumo

11. Matla a modumo ntlheng ea P, e leng 3 m ho tloha mohloling oa modumo, ke 10 ^-4 watt/m ^2. Ntlha ea R e 300 m ho tloha mohloling oa modumo. Haeba matla a moeli I ₀ = 10 ^-12 watt/m ² , joale karolelano ea maemo a matla lintlheng tsa P le R ke…

K. 1: 2

B. 2: 1

C. 2: 3

D. 2: 4

E. 3: 4

Puisano

Hoa tsebahala hore :

Matla a molumo ntlheng ea P (IP ₎ = 10 ^-4 W/m ²

Sebaka sa ntlha P ho tloha mohloling oa molumo (r _P ) = limithara tse 3

Sebaka sa ntlha R ho tloha mohloling oa molumo (r _R ) = limithara tse 300

Matla a Moeli (Io ₎ = 10 ^-12 Watt/ ^m2

Potso : Papiso ea maemo a matla lintlheng tsa P le R (TI _P : TI _R )

Karabo :

Foromo ea kamano pakeng tsa matla le sebaka :

Ke _p r _p ² = Ke _R r _R ²

Matla a molumo ho R :

(10 ^-4 )(3 ² ) = (I _R )(300 ² )

(10 ^-4 )(9) = (I _R )(90000)

9 x 10 ^-4 = (I _R )(9 x 10 ⁴ )

IR ₌ 9 x 10 ^-4 : 9 x 10 ^-4

IR ₌ 10 ^-8

Matla a molumo ntlheng ea R ke 10 ^-8 W/ ^m2.

Papiso ea TI lintlheng tsa P le R :

80 dB: 40 dB

2: 1

Karabo e nepahetseng ke B.

12. Matla a modumo ntlheng ya A, e leng mithara e le 1 ho tloha mohloding wa modumo, ke 10 ^-7 W/m ² . Ntlha ya B e dimithara tse 100 ho tloha mohloding wa modumo. Haeba matla a moedi a le 10 ^-12 W/m ² , karolelano ya maemo a matla ho A le B ke…

K. 5: 3

B. 5: 1

C. 4: 5

D. 4: 3

E. 3: 1

Puisano

Hoa tsebahala hore :

Matla a molumo ntlheng ea A (IA ₎ = 10 ^-7 W/m ²

Sebaka sa ntlha A ho tloha mohloling oa molumo (r _A ) = limithara tse 1

Sebaka sa ntlha B ho tloha mohloling oa molumo (r _R ) = limithara tse 100

Matla a Moeli (Io ₎ = 10 ^-12 Watt/ ^m2

Potso : Papiso ea maemo a matla lintlheng tsa A le B (TI _A : TI _B )

Karabo :

Foromo ea kamano pakeng tsa matla le sebaka :

I _A r _A ² = I _B r _B ²

Matla a molumo ntlheng ea B :

(10 ^-7 )(1 ² ) = (I _B )(100 ² )

(10 ^-7 )(1) = (I _B )(10.000)

1 x 10 ^-7 = (I _B )(1 x 10 ⁴ )

I _B = 10 ^-7 : 10 ⁴

1 _B = 10 ^-11

Matla a molumo ntlheng ea R ke 10 ^-11 W/ ^m2.

Papiso ea IT lintlheng tsa A le B :

50 dB: 10 dB

5: 1

Karabo e nepahetseng ke B.

13. Lintlha tsa A le B li na le sebaka sa 800 m le 400 m ka ho latellana ho tloha mohloling oa molumo. Haeba sebakeng sa A u utloa molumo o nang le matla a 10 ^-3 W/m ² , joale karolelano ea maemo a matla lintlheng tsa A le B ke... (log 2 = 0,3 le I _o = 10 ^-12 W/m ² )

K. 11: 15

B. 15: 11

C. 15: 16

D. 16: 11

E. 16: 15

Puisano

Hoa tsebahala hore :

Matla a molumo ntlheng ea A (IA ₎ = 10 ^-3 W/m ²

Sebaka sa ntlha A ho tloha mohloling oa molumo (r _A ) = limithara tse 800

Sebaka sa ntlha B ho tloha mohloling oa molumo (r _B ) = limithara tse 400

Matla a Moeli (Io ₎ = 10 ^-12 Watt/ ^m2

Log 2 = 0,3

Potso : Papiso ea maemo a matla lintlheng tsa A le B (TI _A : TI _B )

Karabo :

Foromo ea kamano pakeng tsa matla le sebaka :

I _A r _A ² = I _B r _B ²

Matla a molumo ntlheng ea B :

(10 ^-3 )(800 ² ) = (I _B )(400 ² )

(10 ^-3 )(640.000) = (I _B )(160.000)

(10 ^-3 )(64) = (I _B )(16)

(10 ^-3 )(4) = (I _B )(1)

I _B = 4 x 10 ^-3 : 1

1 _B = 4 x 10 ^-3

Matla a molumo ntlheng ea B ke 4 x 10 ^-3 W/ ^m2.

Karolelano ea TI lintlheng tsa P le R ke:

90 dB: 96 dB

15: 16

Karabo e nepahetseng ke C.

Matla le maemo a matla a molumo

14. Tafole ea maemo a matla bakeng sa mohloli o mong le o mong oa molumo.

Mohloli oa molumo	Boemo ba Matla a Molumo (TI)
Molumo oa linonyana tse llang	80 dB
Sirene ea ambulense	100 dB
Sealuma (lehalima)	160 dB

Enjene ea koloi e hlahisa boemo ba matla a molumo ba TI = 70 dB (Io ₌ 10 ⁻¹² Watt m ⁻² ). E le hore molumo oa enjene o hlahise boemo ba matla a lekanang le molumo oa siren ea ambulense, palo ea lienjene tsa koloi tse hlokahalang ke….

Mochini oa A. 20.00
Mochini oa B. 30.00
Mechini ea C. 100.0
D. Mechini e 1.000
Mechini e 3.000 ea E.

Puisano
Hoa tsebahala :
Koloi ea TI = 70 dB
Ambulense TI = 100 dB
I_o = 10^-12 Watt/m²
E botsitsoe : IT ea koloi e lokela ho lekana le IT ea ambulense ka lienjine tse kae tsa koloi?
Jawab :

Ambulense TI = koloi TI + 10 log x
100 = 70 + 10 log x
100 – 70 = 10 log x
30 = 10 log x
30 / 10 = log x
3 = log x
Antilog 3 = x
10³ =x
1000 = x
Karabo e nepahetseng ke D.

15. Mohloli oa molumo o na le boemo ba matla ba 60 dB (Io ₌ 10 ^{- 12} watts m ^{- 2} ). Ha mehloli e 100 ea molumo o tšoanang e utloahala ka nako e le 'ngoe, boemo ba matla a molumo bo hlahang ke ...

A. 62 dB
B. 80 dB
C. 82 dB
D. 100 dB
E. 160 dB

Puisano
Hoa tsebahala :
TI = 60 dB
I_o = 10^-12 W / limithara²
x = 100
E botsitsoe : Mohloli oa molumo oa TI 100?
Jawab :
Mehloli ea molumo ea TI 100 = Mochini oa TI 1 + 10 log x
TI = 60 + 10 log 100
TI = 60 + 10 log 10²
TI = 60 + (2)(10)(log 10)
TI = 60 + 20
TI = 80 dB
Karabo e nepahetseng ke B.

Phello ea Doppler
16. Sebapali sa bolo ea maoto se matha ka lebelo v_p ho ea ho moahloli ea neng a khutsitse ha a ntse a letsa mololi khafetsa ea f_sHaeba lebelo la moea sebakeng seo e le v, joale maqhubu a utluoang ke sebapali a hlophisitsoe joalo ka….

Puisano
Hoa tsebahala :
v_s = 0 (moahloli o khutsitse)
v_p = v_p (e ntle hobane e haufi le mohlodi wa modumo)
f = f_s
v = v
E botsitsoe : mokhoa oa makhetlo oo libapali tsa bolo ea maoto li o utloang ke ofe?
Jawab :

Karabo e nepahetseng ke A.

Mohloli oa lipotso:

Lipotso tsa Fisiks tsa Tlhahlobo ea Naha bakeng sa Sekolo se Phahameng sa Thuto e Phahameng/Sekolo se Phahameng sa Mosebetsi