Mphamvu zomwe zingatheke - mavuto ndi mayankho

1. Mphamvu 4900 Joules imagwiritsidwa ntchito kukweza chinthu cholemera makilogalamu 50 kufika kutalika kwa h. Kodi kutalika kwa h ndi kotani? Kuthamanga chifukwa cha mphamvu yokoka (g) = 9.8 ms ^-2.

Zodziwika:

Kusintha kwa mphamvu yothekera (ΔPE) = 4900 Joules

Kulemera kwa chinthu (m) = 50 kg

Kuthamanga chifukwa cha mphamvu yokoka (g) = 9.8 m/s ²

Kufunidwa: kutalika (Δh)

Yankho:

ΔPE = mg Δh

4900 = (50)(9.8) Δh

4900 = 490 Δh

Δh = mamita 10

Mphamvu ya masika

2. Chithunzi chili pansipa chikuwonetsa ubale pakati pa mphamvu (F) ndi x (kusintha kwa kutalika) kwa kasupe. Ngati kusintha kwa kutalika kwa kasupe ndi 8 cm, kodi mphamvu ya kasupe ndi yotani?

Zodziwika:

Mphamvu (F) = 2 Newton Mavuto ndi mayankho a mphamvu omwe angakhalepo 1

Kusintha kwa kutalika 1 (x) = 1 cm = 1/100 m = 0.01 m

Kusintha kwa kutalika 2 = 8 cm = 8/100 m = 0.08 m

Kufunidwa: Mphamvu ya masika

Yankho:

Chokhazikika cha Spring:

Mphamvu ya masika:

∆PE = 1/2 kx ²

∆PE = 1/2 (200 N/m)(0.08 m) ²

∆PE = (100 N/m)(0.0064 ^m2 )

∆PE = 0.64 Nm

3. Kutengera tebulo ili m'munsimu, F = kulemera kwa chinthu, ∆L = kusintha kwa kutalika kwa kasupe. Kodi ntchito yochitidwa pa kasupe ndi yotani kotero kusintha kwa kutalika kwa kasupe ndi 10 cm?

Zodziwika: Mavuto ndi mayankho a mphamvu omwe angakhalepo 2

Kusintha kwa kutalika kwa kasupe (∆L) = 10 cm = 0.1 m

Akufuna: Ntchito yachitika masika

Yankho:

Chokhazikika cha Spring:

k = F / ∆x = 20 N / 0.04 m = 500 N/m

k = F / ∆x = 30 N / 0.06 m = 500 N/m

k = F / ∆x = 40 N / 0.08 m = 500 N/m

Mphamvu ya Spring ndi 500 N/m

Ntchito imachitika pa kasupe kotero kusintha kwa kutalika kwa kasupe ndi 10 cm:

W = 1/2 k ∆L ² = 1/2 (500 N/m)(0.1 m) ² = (250 N/m)(0.01 m ² ) = 2.5 N m = 2.5 Joules.

4. Chithunzi chili pansipa chikuwonetsa ubale pakati pa mphamvu (F) ndi kusintha kwa kutalika (x). Kodi mphamvu ya mphamvu ya masika ndi yotani kutengera chithunzi chili pansipa?

Zodziwika: Mavuto ndi mayankho a mphamvu omwe angakhalepo 4

F = 40 Newton

Δx = 0.08 m

Kufunidwa: mphamvu ya masika

Yankho:

Chokhazikika cha Spring:

k = F / Δx

Mphamvu ya masika:

PE = ½ k Δx ² = ½ (F/Δx) Δx ² = ½ F Δx

PE = ½ (40) (0.08) = (20) (0.08) = 1.6 Joules

Kodi mphamvu yothekera ndi chiyani?
- yankhoMphamvu yomwe chinthu chili nayo chifukwa cha malo ake kapena momwe chilili. Ndi mphamvu yomwe ili ndi mphamvu yogwira ntchito koma siikuyambitsa kuyenda pakadali pano.
Kodi mphamvu yokoka imadalira bwanji kutalika?
- yankhoMphamvu yokoka imafanana mwachindunji ndi kutalika kwa chinthu pamwamba pa malo ofotokozera. Fomula yake ndi PE $= m g h$ , komwe PE ndi mphamvu yomwe ingakhalepo, $m$ ndi kulemera, $g$ ndi kufulumira kwa mphamvu yokoka, ndipo $h$ ndi kutalika.
N’chifukwa chiyani anthu amanena kuti kasupe wotambasuka kapena wopanikizika ali ndi mphamvu?
- yankho: Pamene kasupe watambasulidwa kapena kukakamizidwa kuchoka pamalo ake ofanana, amasunga mphamvu. Mphamvu imeneyi imatha kugwira ntchito kasupe akabwerera ku malo ake ofanana. Mphamvu yosungidwa iyi imatchedwa mphamvu yokhazikika.
Kodi mphamvu ya chinthu imasintha bwanji ngati yakwezedwa kufika pa msinkhu wake woyambirira kawiri kuposa mphamvu yokoka?
- yankho: Ngati chinthu chakwezedwa kufika pa msinkhu wake woyamba kawiri, mphamvu yake yokoka imawirikiza kawiri. Izi zili choncho chifukwa mphamvu yomwe ingakhalepo imadalira kutalika kwake.
Kodi n'zotheka kuti chinthu chikhale ndi mphamvu yoipa? Fotokozani.
- yankhoInde, mphamvu zomwe zingatheke zitha kukhala zoipa kutengera kusankha kwa malo ofotokozera. Mwachitsanzo, pamavuto a mphamvu zomwe zingatheke, nthawi zambiri timaika maziko ngati opanda mphamvu zomwe zingatheke. Ngati chinthu chili pansi pa malo ofotokozera awa (monga m'chitsime), mphamvu zake zomwe zingatheke zingakhale zoipa poyerekeza ndi malo ofotokozera omwe asankhidwa.
Kodi mphamvu zomwe zingatheke zimagwirizanitsidwa bwanji ndi mphamvu ya kinetic mu closed system?
- yankho: Mu dongosolo lotsekedwa lopanda mphamvu zakunja, mphamvu yonse (kinetic + potential) imakhalabe yokhazikika. Mfundo imeneyi imachokera pa kusunga mphamvu. Pamene mphamvu zomwe zingatheke zikuwonjezeka, mphamvu ya kinetic imachepa, ndipo mosemphanitsa.
Kodi chimachitika ndi chiyani ku mphamvu yokoka ya apulo ikagwa kuchokera mumtengo?
- yankho: Pamene apulo ikugwa, mphamvu yake yokoka imachepa chifukwa ikuyandikira Dziko Lapansi. Mphamvu yomwe yatayikayi imasinthidwa kukhala mphamvu ya kinetic, zomwe zimapangitsa apulo kuyenda mofulumira pamene ikugwa.
N’chifukwa chiyani pendulum imakhala ndi mphamvu zambiri pamene ikugwedezeka?
- yankho: Pamwamba pa kugwedezeka kwake, pendulum imakhala pamalo ake apamwamba kwambiri poyerekeza ndi malo ake opumulira. Izi zikutanthauza kuti ili ndi kutalika kwakukulu ndipo, motero, mphamvu yayikulu yokoka. Pamene ikutsika, mphamvu iyi imasinthidwa kukhala mphamvu ya kinetic.
Kodi chinthu chingakhale ndi mphamvu ngakhale sichili m'munda wa mphamvu yokoka?
- yankhoInde. Mphamvu zomwe zingatheke sizimangopezeka m'malo okoka mphamvu zokha. Mwachitsanzo, kasupe wopanikizika pa malo osungira zinthu zakuthambo (komwe mphamvu yokoka ndi yochepa) amakhalabe ndi mphamvu yokoka. Mofananamo, mphamvu zomwe zili m'malo osungira zinthu zamagetsi zimakhala ndi mphamvu zamagetsi zokha.
Kodi kulemera kwa chinthu kumakhudza bwanji mphamvu yake yokoka?
- yankho: Mphamvu yokoka imafanana mwachindunji ndi kulemera kwa chinthu. Ngati muchulukitsa kawiri kulemera kwa chinthu, mphamvu yake yokoka (yomwe ili pamtunda womwewo) idzawonjezekanso kawiri.