Amandla angenzeka - izinkinga nezixazululo

Amandla angenzeka - izinkinga nezixazululo

Amandla adonsela phansi anamandla

1. Amandla angu-4900 Joules asetshenziswa ukuphakamisa into enesisindo esingu-50 kg ibe ukuphakama okungu-h. Kuyini ukuphakama okungu-h? Ukusheshisa ngenxa yamandla adonsela phansi (g) = 9.8 ms ^-2.

Kwaziwa:

Ushintsho lwamandla angase abe khona (ΔPE) = 4900 Joules

Isisindo sento (m) = 50 kg

Ukusheshisa ngenxa yamandla adonsela phansi (g) = 9.8 m/s ²

Okufunwayo: ukuphakama (Δh)

Isixazululo:

ΔPE = mg Δh

4900 = (50)(9.8) Δh

4900 = 490 Δh

Δh = amamitha ayi-10

Amandla angase abe khona entwasahlobo

2. Igrafu engezansi ikhombisa ubudlelwano phakathi kwamandla (F) kanye no-x (ushintsho lobude) besiphethu. Uma ushintsho lobude besiphethu lungamasentimitha angu-8, iyini amandla angase abe khona esiphethu?

Kwaziwa:

Amandla (F) = 2 Newton

Ushintsho lobude 1 (x) = 1 cm = 1/100 m = 0.01 m

Ushintsho lobude 2 = 8 cm = 8/100 m = 0.08 m

Okufunwayo: Amandla entwasahlobo

Isixazululo:

Okungaguquki kwentwasahlobo:

Amandla angase abe khona entwasahlobo:

∆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. Ngokusekelwe kuthebula elingezansi, u-F = isisindo sento, u-∆L = ushintsho lobude bentwasahlobo. Uyini umsebenzi owenziwe entwasahlobo ukuze ushintsho lobude bentwasahlobo lube ngu-10 cm.

Kwaziwa:

Ushintsho lobude bentwasahlobo (∆L) = 10 cm = 0.1 m

Okufunwayo: Umsebenzi owenziwe entwasahlobo

Isixazululo:

Okungaguquki kwentwasahlobo:

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

I-constant yaseNtwasahlobo ingu-500 N/m

Umsebenzi wenziwa entwasahlobo ngakho-ke ushintsho lobude bentwasahlobo luyi-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. Igrafu engezansi ikhombisa ubudlelwano phakathi kwamandla (F) kanye noshintsho lobude (x). Iyini amandla entwasahlobo asekelwe kugrafu engezansi.

Kwaziwa:

F = 40 Newton

Δx = 0.08 m

Kufunwa: amandla entwasahlobo

Isixazululo:

Okungaguquki kwentwasahlobo:

k = F / Δx

Amandla angase abe khona entwasahlobo:

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

I-PE = ½ (40)(0.08) = (20)(0.08) = 1.6 Joule

1. Iyini amandla angase abe khona?
   • Impendulo: Amandla angase abe amandla into enawo ngenxa yesikhundla noma isimo sayo. Amandla angase abe namandla okwenza umsebenzi kodwa angabangeli ukunyakaza okwamanje.
2. Amandla adonsela phansi ancike kanjani ekuphakameni?
   • Impendulo: Amandla adonsela phansi ahambisana ngqo nokuphakama kwento ngaphezu kwephuzu lokubhekisela. Ifomula yi-PE$=mgh$, lapho i-PE ingamandla angaba khona, $m$ isisindo, $g$ ukusheshisa kwamandla adonsela phansi, futhi $h$ ukuphakama.
3. Kungani kuthiwa isiphethu esinwetshiwe noma esicindezelwe sinamandla angase abe khona?
   • Impendulo: Uma isiphethu seluliwe noma sicindezelwe endaweni yaso yokulingana, sigcina amandla. Lawa mandla anamandla okwenza umsebenzi lapho isiphethu sibuyela esimweni saso sokulingana. Lawa mandla agciniwe abizwa ngokuthi amandla anamandla okunwebeka.
4. Amandla angaba khona ento ashintsha kanjani uma ephakanyiswe kabili ukuphakama kwawo kokuqala ensimini yamandla adonsela phansi?
   • Impendulo: Uma into iphakanyiswa kabili ukuphakama kwayo kokuqala, amandla ayo adonsela phansi aphindeka kabili. Lokhu kungenxa yokuthi amandla angase abe khona ancike ngokulingana ekuphakameni.
5. Kungenzeka yini ukuthi into ibe namandla angenamandla angemahle? Chaza.
   • Impendulo: Yebo, amandla angase abe negative kuye ngokuthi indawo yokubhekisela ikhethwe kanjani. Isibonelo, ezinkingeni zamandla angase abe negative, sivame ukubeka isisekelo njengengenawo amandla angase abe negative. Uma into ibingaphansi kwaleli phuzu lokubhekisela (njengasemgodini), amandla ayo angase abe negative uma kuqhathaniswa nereferensi ekhethiwe.
6. Amandla angase abe khona ahlobene kanjani namandla e-kinetic ohlelweni oluvaliwe?
   • Impendulo: Esimisweni esivaliwe esingenawo amandla angaphandle, amandla aphelele (kinetic + potential) ahlala engaguquki. Lesi simiso sisekelwe ekulondolozweni kwamandla. Njengoba amandla angase akhule, amandla e-kinetic ayancipha, futhi okuphambene nalokho.
7. Kwenzekani emandleni adonsela phansi e-apula uma liwa esihlahleni?
   • Impendulo: Njengoba i-apula liwa, amandla alo adonsela phansi ayancipha ngoba lisondela eMhlabeni. La mandla alahlekile aguqulwa abe amandla e-kinetic, okwenza i-apula lihambe ngokushesha njengoba liwa.
8. Kungani i-pendulum inamandla amakhulu kakhulu lapho ifinyelela phezulu ekujikeni kwayo?
   • Impendulo: Lapho ifinyelela esicongweni sokujika kwayo, i-pendulum isendaweni yayo ephezulu uma iqhathaniswa nendawo yayo yokuphumula. Lokhu kusho ukuthi inokuphakama okuphezulu kakhulu, ngakho-ke, amandla aphezulu adonsela phansi. Njengoba ijika phansi, la mandla aguqulwa abe amandla e-kinetic.
9. Ingabe into ingaba namandla angase abe khona ngisho noma ingekho ensimini yamandla adonsela phansi?
   • Impendulo: Yebo. Amandla angase atholakale awagcini nje emasimini adonsela phansi. Isibonelo, isiphethu esicindezelwe esiteshini sasemkhathini (lapho imiphumela yamandla adonsela phansi incane khona) sisenamandla angase aqine. Ngokufanayo, amashaja ensimini kagesi anamandla angase atholakale kagesi.

10. Ubunzima bento buyithinta kanjani amandla ayo adonsela phansi?

    • Impendulo: Amandla adonsela phansi alingana ngqo nobunzima bento. Uma uphinda kabili ubunzima bento, amandla ayo adonsela phansi (aphakeme ngendlela efanayo) nawo azophindeka kabili.