Wakali wa Physics manasemaje juu ya hili?

Mrimi said:

Habari ya mwaka mpya waungwana.
Nimekuwa nikitatizwa sana na hili jambo,naombeni wenye uelewa wanisaididie ili na wengine wenye interest ya kujua wanufaike.

Nataka kujua,ile "tochi" ya matrafiki wa barabarani inatumia principle gani kudetect speed ya gari.Je ni image ya ile moving object(gari) au change in sound frequency ya object towards an observer (ile tochi)? Au ni nini hasa?

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Haiwezi kuwa doppler effect kwa sababu gari zinaweza kufika kwenye eneo la proximity ya camera hata zikiwa zaidi ya mbili au tatu. Doppler effect inashughulika na sauti ya kitu, hivyo katika mazingira kama hayo sidhani kama hizo kamera ziko sophisticated kiasi hicho cha kuwa na uwezo wa kuchanganua frequencies za object tofauti tofauti na hatimaye kuweza ku-judge kuwa hii frequency ni ya gari hii na siyo ya ile. Sababu gari zote zaweza kuwa hata Yutong 4, mbili zime-overspeed halafu mbili zimekimbia kawaida. Katika mazingira kama haya, ukitumia doppler effect, utajuaje? Nadhani inatumia speed ya object, ila sina uhakika, I'm just arguing from logic!

Laser Speed Detection and LIDAR (LIght Detection and Ranging)
LIDAR measures the vehicle's speed by sending out two laser pulses and calculating the difference in time it takes to detect the pulses of light reflected from the target, your car
LIDAR has the distinct advantage of being able to pick out one vehicle in a cluttered stream of traffic; your vehicle cannot be mistaken for another vehicle unlike radar, which has a broader pulse. It can also be used over a large distance, which makes it even more difficult to spot. License plates are typically the strongest LIDAR target, as they are covered in a retro reflective material that returns light back its source with a bare minimum of scattering.

How LIDAR Works

Light travels from the LIDAR gun at about 3x10[SUP]8[/SUP]meters/second, or 0.3 meters per nanosecond. After the light hits the target, it is reflected back towards the source. The laser determines distance by calculating how far a returning photon has traveled to and from a target:

Distance = [Speed of Light x Time of Flight] / [2]
1. Laser gun generates an optical pulse.
2. The pulse travels from the laser gun to the target and back to the gun.
3. LIDAR system measures the time of flight from the start pulse to the return pulse.
4. Time measurement is converted to a distance by using the formula above.
The LIDAR gun then sends out a second pulse and finds the distance again, as well as the time between the two pulses. Using the following formula, it can determine your speed.
Speed = [Change in Distance (Dx)]/ [Change in Time (Dt)]
The LIDAR system then determines your speed by the above formula.
A laser gun can determine your speed very quickly, about 1,000 times per second!

Mrimi said:

Sina hakika ni wangapi tutakuwa tumenufaika na somo hili,ila niseme tu kwamba kwa upande wangu nimenufaika kuliko hata nilivyotarajia.

Asante sana:

Gaijin
Kalumbesa
KXY

Long live Jamii Forums.

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Siku nyingine uanze na @ kisha jina ku-mention mkuu Mrimi
shukrani zilikuwa zimenipita, asante nawe pia kwa kutufungua macho.

Gaijin said:

Kama speed ya vehicle ni negative (-100) basi speed tochi ni positive (+5) kwa sababu inakwenda kwenye upande unaokinzana na gari.

Ukitaka kutafuta relative velocity, maana yake ni kuwa unatafuta tofauti ya velocity baina ya hivyo vitu viwili vinavyotembea hivyo utalazimika kuchukua speed moja unatoa speed nyengine kwa hiyo itakuwa -100 - (+5)= -105 ambayo unapunzungumzia relative velocity alama ya + au - inaonyesha tu direction

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Unafaa sana kuwa mwalimu, hapo kwenye issue ya direction ndo nilikuwa napatafuta..! You put it simple and clear

Kinyungu said:

Gaijin amesaidia kufafanua hapo chini..hebu soma labda utaelewa

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Nimeelewa sana kumbe relative velovity ni tofauti ya velocity mbili au zaidi halafu una-consider direction of those objects. Kuanzia sasa hivi trafic watanikoma, sintolipa overspeed ya which does not exceed 5km/hr. Lazima nitawambia tutoe torch speed yao angalau 5Km/hr.!

KXY said:

Wataalamu watuambie kama ni hii:

LIDAR (Light Detection And Ranging, also LADAR) is an optical remote sensing technology that can measure the distance to, or other properties of, targets by illuminating the target with laser light and analyzing the backscattered light

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mkuu soma hapo chini


www.delonixradar.com.au/south-australia/

LIDAR ni inayotumia laser lakini kuna mbinu nyingine ya kutuma radar kwahio wote waliokupa majina hawajakosea ila inayotumea radar na sio laser haiitwi LIDAR kwahio mkuu nadhani tutakuwa accurate tukiziita handled speed detectors

Gaijin
Mrimi
Karumbesa
Kifarutz
Samaritan
MAKANYAnga

sun wu said:

mkuu soma hapo chini


Police Radar Laser & Speed cameras in South Australia, detectors, jammers, fines

LIDAR ni inayotumia laser lakini kuna mbinu nyingine ya kutuma radar kwahio wote waliokupa majina hawajakosea ila inayotumea radar na sio laser haiitwi LIDAR kwahio mkuu nadhani tutakuwa accurate tukiziita handled speed detectors

Gaijin
Mrimi
Karumbesa
Kifarutz
Samaritan
MAKANYAnga

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Nimekupata mkuu na upo sahihi na kweli sijaona jibu la jina sahihi la 'tochi', majibu mengi yaliegemea swali la mtoa mada

Mrimi said:

Nataka kujua,ile "tochi" ya matrafiki wa barabarani inatumia principle gani kudetect speed ya gari.Je ni image ya ile moving object(gari) au change in sound frequency ya object towards an observer (ile tochi)? Au ni nini hasa?

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Radar guns zinaitwa tochi? :confused2:

still loading........:confused2:!!!

Makanyaga said:

Haiwezi kuwa doppler effect kwa sababu gari zinaweza kufika kwenye eneo la proximity ya camera hata zikiwa zaidi ya mbili au tatu. Doppler effect inashughulika na sauti ya kitu, hivyo katika mazingira kama hayo sidhani kama hizo kamera ziko sophisticated kiasi hicho cha kuwa na uwezo wa kuchanganua frequencies za object tofauti tofauti na hatimaye kuweza ku-judge kuwa hii frequency ni ya gari hii na siyo ya ile. Sababu gari zote zaweza kuwa hata Yutong 4, mbili zime-overspeed halafu mbili zimekimbia kawaida. Katika mazingira kama haya, ukitumia doppler effect, utajuaje? Nadhani inatumia speed ya object, ila sina uhakika, I'm just arguing from logic!

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Hizo ni changamoto ya mashine wanazotumia traffic wetu manake hazionyeshi kiusahihi ni gari gani imehusika. Nakumbuka kuna jamaa alibishana nao wamhakikishie kama speed inayooneshwa kwenye screen yao ni ya gari yake na siyo mengine aliyokuwa ameongozana nayo ikashindikana.

Nyani Ngabu said:

Radar guns zinaitwa tochi? :confused2:

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Watu wa majuu bwana? Yaani hajui hata kuna vitu vidogovidogo kama tochi, yeye anajua radar tu sababu alishazoea kupanda ndege.

Nikuulize swali rafiki yangu, hivi wewe tuseme unapokuja likizo kijijini kwenu kule Shinyanga, wale wazee wa kijijini ambao wakati mwingine wanavaa nguo zinanukia mafuta ya mtindi mbichi wa ng'ombe sababu wakati mwingi wanashinda wanahangaika na ng'ombe/mifugo siku nzima, HUWA UNAONGEA NAO KWELI MNAELEWANA?

Makanyaga said:

Watu wa majuu bwana?

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Watu wa majuu ndiyo kina nani? Halafu hapo umeuliza ama umeshangaa? Hueleweki.

Yaani hajui hata kuna vitu vidogovidogo kama tochi,

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Nani hajua kama kuna tochi?

yeye anajua radar tu sababu alishazoea kupanda ndege.

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Ni nani huyo?

Nikuulize swali rafiki yangu,

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Acha kujipendekeza. Mimi siyo rafiki yako. Kwanza sikujui.

hivi wewe tuseme unapokuja likizo kijijini kwenu kule Shinyanga,

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Shinyanga ni mkoa, siyo kijiji.

wale wazee wa kijijini ambao wakati mwingine wanavaa nguo zinanukia mafuta ya mtindi mbichi wa ng'ombe sababu wakati mwingi wanashinda wanahangaika na ng'ombe/mifugo siku nzima,

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Uliwahi kuwanusa?

HUWA UNAONGEA NAO KWELI MNAELEWANA?

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Niongee nao kwa minajili ipi?

Mrimi said:

Hapa ndipo ninazidi kuchanganyikiwa,au wenzangu nyie mnaonaje? Image au change in sound freq.(doppler effect)?
Hivi kwanza kale kakitu kanaitwaje kitalamu,ili tujaribu hata kugoogle basi!

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Radar speed trap inaitwa kaka ni kwamba inatuma frequency na zinakuwa reflected kurudi kwake baada ya kugonga gari

kwa hiyo hizo reflected frequencies ndo zinatumika kujua speed ya gari
hapa kidogo lazima uwe umepiga doppler effect advanced level physics

Hivi kuna mtu alishakamatwa na tochi usiku? Au ni mchana tu?

Sent from my GT-P7500 using Tapatalk 2

Mkuu, Wikipedia huwa inasaidia sana. Ila ukisoma hapo jambo, basi kalitafute tena sehemu nyingine.

Hebu soma hapa: Radar gun - Wikipedia, the free encyclopedia

[h=3]Doppler effect[/h]Speed guns use Doppler radar to perform speed measurements.
Radar speed guns, like other types of radar, consist of a radio transmitter and receiver. They send out a radio signal in a narrow beam, then receive the same signal back after it bounces off the target object. Due to a phenomenon called the Doppler effect, if the object is moving toward or away from the gun, the frequency of the reflected radio waves when they come back is different from the transmitted waves. From that difference, the radar speed gun can calculate the speed of the object from which the waves have been bounced. This speed is given by the following equation:
where c is the speed of light, f is the emitted frequency of the radio waves and Δf is the difference in frequency between the radio waves that are emitted and those received back by the gun. This equation holds precisely only when object speeds are low compared to that of light, but in everyday situations, the velocity of an object is directly proportional to this difference in frequency.
By rearranging terms we can see that Δf is proportional to the absolute frequency as well as the object velocity. Any change in f, the operating frequency in a radar gun, will produce a change in the calibrated relation between Δf and v.



Ila hiyo ni moja ya RADAR maana zipo za aina nyingi .....

Gaijin said:

Katika lugha ya Kiingereza inaitwa "LIDAR" ikiwa ni kifupi cha "Light Detection And Ranging"

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Sio LIDAR ni RADAR yaani Radio Detection and Ranging inafanya kazi kama radar za "chenge" yaani zile wanazotumia aviation au military au meli kubwa zote principle ni sawa ila torchi ya police inashikwa mkononi wakati inapaswa kuwekwa kwenye stand yake kuachieve better result.

Sikonge said:

Mkuu, Wikipedia huwa inasaidia sana. Ila ukisoma hapo jambo, basi kalitafute tena sehemu nyingine.

Hebu soma hapa: Radar gun - Wikipedia, the free encyclopedia

Doppler effect

Speed guns use Doppler radar to perform speed measurements.
Radar speed guns, like other types of radar, consist of a radio transmitter and receiver. They send out a radio signal in a narrow beam, then receive the same signal back after it bounces off the target object. Due to a phenomenon called the Doppler effect, if the object is moving toward or away from the gun, the frequency of the reflected radio waves when they come back is different from the transmitted waves. From that difference, the radar speed gun can calculate the speed of the object from which the waves have been bounced. This speed is given by the following equation:
where c is the speed of light, f is the emitted frequency of the radio waves and Δf is the difference in frequency between the radio waves that are emitted and those received back by the gun. This equation holds precisely only when object speeds are low compared to that of light, but in everyday situations, the velocity of an object is directly proportional to this difference in frequency.
By rearranging terms we can see that Δf is proportional to the absolute frequency as well as the object velocity. Any change in f, the operating frequency in a radar gun, will produce a change in the calibrated relation between Δf and v.



Ila hiyo ni moja ya RADAR maana zipo za aina nyingi .....

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Sikonge;
Nice stuff. So, these RADARS use the doppler effect to calculate the speed of a moving object! Very interesting. I'm just a "poor practical oriented physics scholar"!
Thanx for your info!

Hivi Kuna app yoyote unaweza tumia ku detect sehemu zenye hizo tochi?

Kinyungu said:

Ile tochi inapima relative speed. Anapoielekeza kwako halafu kwa mfano wewe ukawa kwenye speed 100km/hr tuna-asume ile tochi iko stationary hivyo speed yake ni zero i.e 0km/hr hivyo inachofanya ile tochi inatafuta relative speed kwa kutoa negative ya speed yako yaani 0km/hr-(-100km/hr)=100km/hr.

Lakini kwa sababu wale maaskari huwa wanaificha ile tochi na kuielekeza kwako ghafla hicho kitendo kinafanya hiyo tochi nayo iwe kwenye speed labda tuseme 5km/hr hivyo kama speed limit ilitakiwa iwe 100km/hr akikuelekezea kwako ukawa kwenye speed 100km/hr anakuwa amepata relative speed ya 5km/hr-(-100km/hr)=105km/hr kwa hiyo unakuwa ume-over speed!

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mkuu tochi inakuwaje katka speed nayo?au ni movable?

Makanyaga said:

Sikonge;
Nice stuff. So, these RADARS use the doppler effect to calculate the speed of a moving object! Very interesting. I'm just a "poor practical oriented physics scholar"!
Thanx for your info!

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Well, seems like uko vizur mbona Doppler effect nlisoma High-school na nahis nmeshasahau vingi[emoji28]