ʻO ka mokulele inclined - nā pilikia a me nā hoʻonā

ʻO ka mokulele inclined - nā pilikia a me nā hoʻonā

1. ʻO ke kaumaha o ka poloka he 5 kg, ʻo ka wikiwiki ma muli o ke koʻikoʻi = 9.8 m/s² ^, tan 37 ^o = 3/4. He aha ka wikiwiki o ka poloka?

pāʻoihana

ʻIke ʻia:

ka nuipaʻa (m) = 5 kg

ka wikiwiki ma muli o ke koʻikoʻi (g) = 10 m/s ²

kaumaha (w) = mg = (5)(10) = 50 N

x = 3

ʻO ke kiʻekiʻe o ka mokulele inclined (y) = 4

ʻO ka lōʻihi o ka ʻili mokulele inclined (l) = 5

Makemake ʻia : ka wikiwiki o ka poloka (a)?

Lōlā:

Hoʻolalelale ʻia ka poloka e ka ikaika o w _x . He laumania ka mokulele i hoʻokiʻekiʻe ʻia no laila ʻaʻohe ikaika friction.

w _x = w sin θ = (w)(y / z)

wx = (50)(4/5 ₎

wx = ₄₀ Newton

Ka wikiwiki o ka poloka (a)?

ΣF = ma

wx ₌ ma

40 = (5) a

a = 40 / 5

a = 8 m/s ²

2. He poloka i hoʻomaha mua ʻia, a laila hoʻolalelale ʻia i luna e like me ka ʻili o ka mokulele inclined. ʻO ke kaumaha o ka poloka = 8 kg, ke koina o ka friction static µs ₌ 0.5 a me ke kihi θ = 45 ^o . He aha ka nui o ka ikaika F i mea e hoʻolalelale ʻia ai ka poloka.

ʻIke ʻia:

Ka helu o ka haʻalulu paʻa (µs ₎ = 0.5

Kihi (θ) = 45 ^o

Ka wikiwiki ma muli o ke koʻikoʻi (g) = 10 m/s ²

Ka nuipa o ka poloka (m) = 8 kg

Kaumaha poloka (w) = mg = (8 kg)(10 m/s ² ) = 80 kg m/s ² = 80 Newtons

Makemake ʻia: Ka nui o ka ikaika F

Lōlā:

Hoʻomaka poloka e hoʻolalelale inā F ≥ w_x + f_s.

ʻĀpana kaulike o ke kaumaha :

w _x = w hewa θ = (80)(hala 45) = (80)(0.5√2) = 40√2

ʻĀpana kaulike o ke kaumaha:

w _y = w cos θ = (80)(cos 45) = (80)(0.5√2) = 40√2

Ka ikaika maʻamau :

N = w _y = 40√2

Ka ikaika o ka haʻalulu paʻa:

f _s = µ _s N = (0.5)(40√2) = 20√2

Ka nui o ka ikaika F:

F ≥ w _x + f _s

F ≥ 40√2 + 20√2

F ≥ 60√2 Newton

3. ʻO ke kaumaha o ka poloka he 8 kg. ʻO ka ikaika liʻiliʻi loa e pono ai e paʻa i ka poloka i ʻole e paheʻe ka poloka i lalo he … (sin 37 ^o = 0.6, cos 37 ^o = 0.8, g = 10 ms ^-2 , µ _k = 0.1)

ʻIke ʻia:

Ka nuipa o ka poloka (m) = 8 kg

Ka wikiwiki ma muli o ke koʻikoʻi (g) = 10 m/s ²

Kaumaha o ka poloka (w) = mg = (8)(10) = 80 Newtons

Sin 37 ^o = 0.6

Cos 37 ^o = 0.8

Ka helu o ka haʻalulu kinetic (µ _k ) = 0.1

Ka ikaika maʻamau (N) = w _y = w cos 37 ^o = (80)(0.8) = 64 Newtons

Makemake ʻia: Ka nui o ka ikaika F

Lōlā:

ʻAʻole e paheʻe ka poloka i lalo inā ʻo F = w _x

ʻĀpana pae o ke kaumaha e kūlike ana me ka ʻili mokulele i hoʻohaʻahaʻa ʻia:

w _x = w hewa θ = (80)(hala 37) = (80)(0.6) = 48

f _k = µ _k N = (0.1)(64) = 6.4

ʻO ka palena iki o ka ikaika F i ʻole e paheʻe i lalo ka poloka:

F + _fk – wx ₌ 0

F = w _x – f _k = 48 – 6.4 = 41.6 Newtons

4. Ua huki ʻia kahi poloka 5-kg ma kahi mokulele hilig ʻino e ka ikaika o 71 N (g = 10 ms ^-2 , sin 37 ^o = 0.6, cos 37 ^o = 0.8). Inā ʻo ke koina o ka ikaika friction ma waena o ka poloka a me ka mokulele hilig he 0.4, he aha ka wikiwiki o ka poloka.

ʻIke ʻia:

Ka nuipa o ka mea (m) = 5 kg

Ka wikiwiki ma muli o ke koʻikoʻi (g) = 10 m/s ²

ke kaumaha o ka poloka (w) = mg = (5)(10) = 50 Newtons

Ikaika F = 71 Newton

Sin 37 ^o = 0.6

Cos 37 ^o = 0.8

Ka helu o ka haʻalulu = 0.4

Makemake ʻia : Ka wikiwiki o ka poloka (a)

Lōlā:

ʻĀpana kaulike o ke kaumaha :

w _x = w hewa θ = (50)(hala 37) = (50)(0.6) = 30

ʻĀpana kaulike o ke kaumaha :

w _y = w cos θ = (50)(cos 37) = (50)(0.8) = 40

Ka ikaika maʻamau:

N = w _y = 40

Ka ikaika o ka haʻalulu kinetic:

f _k = µ _k N = (0.4)(40) = 16

Ka ikaika ʻupena:

∑F = F – w _x – f _k = 71 – 30 – 16 = 25 Newtons

Ka wikiwiki o ka mea:

a = ∑F / m = 25 / 5 = 5 m/s ²

5. He pahu 500-N i hāpai ʻia i ke kalaka ma o kahi mokulele inclined, e like me ka mea i hōʻike ʻia ma ke kiʻi ma lalo. Inā he 1.5 mika ke kiʻekiʻe o ke kalaka, e hoʻoholo i ka nui o ka ikaika e hoʻoneʻe ai i ka pahu.

ʻIke ʻia:

ke kaumaha o ka pahu (w) = 500 Newtons

ke kiʻekiʻe o ke kalaka (h) = 1.5 mika

ka lōʻihi o ka mokulele hilig (l) = 3 mika

Makemake ʻia: Ka nui o ka ikaika e hoʻoneʻe ai i ka pahu (F)

Lōlā:

Sin θ = opp / hyp = 1.5 mika / 3 mika = 1.5 / 3 = 0.5

Ka ikaika (F) e pono ai e hoʻoneʻe i ka pahu, e like me ka ʻāpana kaulike o ke kaumaha e kūlike ana me ka mokulele inclined (w _x ).

w _x = w hewa θ = (500 N)(0.5) = 250 N

1. He aha ka mokulele ʻākau, a pehea e maʻalahi ai ka hana?
   • paneʻO kahi mokulele inclined he ʻili pālahalaha i hoʻonohonoho ʻia ma kahi kihi (ʻaʻole kahi kihi ʻākau) i kahi ʻili ākea. Hoʻomaʻalahi ia i ka hana ma ka ʻae ʻana i kahi ikaika e hoʻopili ʻia ma kahi mamao lōʻihi e lanakila ai i kahi ikaika resistive, e hōʻemi pinepine ana i ka nui o ka ikaika e pono ai e hāpai a hoʻohaʻahaʻa paha i kahi mea.
2. Pehea ka hopena o ke kihi o ka hili ʻana i ka ikaika e pono ai e hoʻoneʻe i kahi mea i luna o ka mokulele?
   • paneʻO ke kiʻekiʻe o ke kihi o ka hilig, ʻo ka nui o ka ikaika e pono ai e hoʻoneʻe i kahi mea i luna o ka mokulele. I ka emi ʻana o ke kihi, emi ka ikaika e pono ai akā ua hoʻopili ʻia ma kahi mamao aku.
3. No ke aha i maʻalahi ai ka pahu kaumaha i luna o kahi alapiʻi ma mua o ka hāpai pololei ʻana i luna?
   • paneʻO ka hoʻokuke ʻana i kahi pahu i luna o kahi alapiʻi (kahi mokulele inclined) e puʻunaue i ke kaumaha o ka pahu ma kahi mamao aku, e hōʻemi ana i ka ikaika e pono ai i kēlā me kēia manawa. ʻO ka hāpai pololei ʻana i luna e pono ai ke pale aku i ke kaumaha piha o ka pahu, e pono ai ka ikaika nui aʻe.
4. Pehea e pili ai ka lōʻihi o ka mokulele hilig i ka ikaika e pono ai e hoʻoneʻe i kahi mea i luna o ka mokulele?
   • paneʻO ka lōʻihi o ka mokulele inclined (no ke kiʻekiʻe paʻa), ʻo ka emi ʻana o ka ikaika e pono ai e hoʻoneʻe i kahi mea i luna o ka mokulele. Eia nō naʻe, pono e hoʻopili ʻia ka ikaika ma kahi mamao aku.
5. Inā hoʻokomo ʻia ka friction ma luna o ka mokulele i hoʻohihi ʻia, pehea lā e hoʻopilikia ai i ka neʻe ʻana o kahi mea ma luna ona?
   • pane: Kūʻē ka haʻihaʻi i ka neʻe ʻana o ka mea. Inā e hoʻokuke ʻia ana kahi mea i luna o ka mokulele i hoʻohaʻahaʻa ʻia, hana ka haʻihaʻi i lalo, e hoʻonui ana i ka ikaika e pono ai e hoʻoneʻe i ka mea. Inā e neʻe ana kahi mea i lalo o ka mokulele, hoʻolohi ka haʻihaʻi i kona iho ʻana.
6. No ke aha e hoʻohana ai nā limahana i nā mokulele iʻe e hoʻouka i nā mea kaumaha ma luna o nā kalaka?
   • paneʻO ka hoʻohana ʻana i kahi mokulele hilig (ramp) e hiki ai i nā limahana ke hoʻohana i ka ikaika liʻiliʻi ma kahi mamao e hoʻouka i nā mea kaumaha, e ʻoi aku ka maʻalahi o ka hana a emi ka paʻakikī ma mua o ka hāpai ʻana i nā mea i luna.
7. Pehea e pili ai ke kaumaha o kahi mea i kona ʻano e paheʻe i lalo ma kahi mokulele hilig?
   • paneʻO ka ʻāpana o ke kaumaha o ka mea e hana like ana me ka ʻili o ka mokulele inclined e hoʻoulu ai iā ia e paheʻe. ʻO ke kaumaha o ka mea, ʻo ka nui o kēia ʻāpana o ke kaumaha, a pēlā, ʻo ka nui o ke ʻano o ka mea e paheʻe i lalo.
8. He aha ke kuleana o ka ikaika maʻamau ma kahi mokulele hilig?
   • paneHana ka ikaika maʻamau i ka ʻili o ka mokulele inclined. ʻO ia ke kuleana no ka nui o ka ikaika frictional ma waena o ka mea a me ka mokulele no ka mea, ʻo ka friction maʻamau ka like me ka ikaika maʻamau.
9. No ke aha e kau ʻia ai ke one a i ʻole ka grit ma luna o kahi mokulele hilig i ka wā hau?
   • paneHoʻonui ke one a i ʻole ka ʻili lepo i ka ikaika friction ma waena o ka mokulele inclined a me nā mea (e like me nā kāmaʻa a i ʻole nā ​​​​​​kaʻa) e pili ana me ia. Kōkua kēia friction i hoʻohui ʻia i ka pale ʻana i ka paheʻe ʻana i ka wā hau a pulu paha.
10. Inā ʻōwili ʻia ka pōpō i luna ma kahi mokulele hilig a laila ʻōwili hou i lalo, e hiki anei ia i kona wikiwiki mua i ka manawa e hoʻi ai i kona wahi hoʻomaka, me ka nānā ʻole i ke kū'ē ʻana o ka ea a me ka friction?

• paneʻAe, i ka loaʻa ʻole o ke kū'ē ʻana o ka ea a me ka friction, e hoʻololi piha ʻia ka ikehu hiki o ka pōpō ma kona wahi kiʻekiʻe loa i ka ikehu kinetic i kona iho ʻana, e ʻae ana iā ia e hiki i kona wikiwiki mua i ka manawa e hoʻi ai i kona wahi hoʻomaka ma muli o ka mālama ʻana i ka ikehu.