Laʻana o nā nīnau Impulse

4 mau laʻana o nā nīnau hoʻoikaika

1. Hāʻule kūʻokoʻa kahi pōpō me ke kaumaha o 0,5 kg mai ke kiʻekiʻe o h ₁ = 7,2 m ma luna o ka papahele a lele i ke kiʻekiʻe o h ₂ = 3,2 m. Inā ʻo ka wikiwiki ma muli o ke koʻikoʻi he 10 ms ^-2 , ʻo ka impulse e hana ana ma ka pōpō...

A. 2,0 Ns

B. 3,0 Ns

C. 10 Ns

D. 40 Ns

E. 80 Ns

Pahana

Ua ʻike ʻia :

Ka nuipa o ka pōpō (m) = 0,5 kg

ʻO ke kiʻekiʻe o ka pōpō hāʻule manuahi (h ₁ ) = 7,2 mika

ʻO ke kiʻekiʻe o ka pōpō lele (h ₂ ) = 3,2 mika

Ka wikiwiki o ka umekaumaha o ka Honua (g) = 10 m/s ²

Nīnau ʻia : Ka hana ʻana o ka impulse ma ka pōpō

Pane :

ʻO ka wikiwiki o ka pōpō ma mua pono o ka hopena (v)_o)

E helu i ka wikiwiki o ka pōpō ma mua pono o ka pā ʻana me ka hoʻohana ʻana i ke ʻano hāʻule manuahi. No ke kiʻekiʻe (h) = 7,2 mika, ka wikiwiki ma muli o ke koʻikoʻi (g) = 10 m/s ² a me ka wikiwiki hope loa ma mua pono o ka pā ʻana i ka papahele, e hoʻohana i ke ʻano v ² = 2 gh

v _o ² = 2(10)(7,2) = 144

v _o = 2(10)(7,2) = 12 m/s

ʻO ka wikiwiki o ka pōpō ma mua o ka pā ʻana (v _o ) he -12 m/s. Hōʻike wale ka hōʻailona maikaʻi ʻole i ke kuhikuhi.

ʻO ka wikiwiki o ka pōpō ma hope koke iho o ke kuʻi ʻana (v)_t)

E helu i ka wikiwiki o ka pōpō ma hope koke iho o ke kuʻi ʻana me ka hoʻohana ʻana i ke ʻano no ka neʻe ʻana i luna. Hāʻawi ʻia ke kiʻekiʻe (h) = 3,2 mika, ka wikiwiki o ka umekaumaha (g) = -10 m/s ² , ka wikiwiki hope loa ma ke kiʻekiʻe loa (v _t ² ) = 0 a me ka wikiwiki mua ma hope koke iho o ke kuʻi ʻana i ka papahele e noi ʻia, no laila e hoʻohana i ke ʻano v _t ² = v _o ² + 2 gh

vt ₂ = v _o ^{2 + 2} gh

0 = v _o ² + 2 (-10)(3,2)

v _o ² = 64

v _o = √64 = 8 m/s

ʻO ka wikiwiki o ka pōpō ma hope o ke kuʻi ʻana (vt ₎ he 8 m/s

Ka hana ʻana o ka impulse ma ka pōpō (I)

Hoʻomaulia ʻia ka impulse me ka hoʻohana ʻana i ke ʻano o ka impulse-momentum theorem.

Impulse (I) = ka loli o ka momentum (Δp)

I = m (v _t – v _o ) = (0,5)(8-(-12)) = (0,5)(8 + 12) = 0,5(20) = 10 Newton kekona

ʻO C ka pane pololei.

2. Hāʻule kūʻokoʻa kahi pōpō ping pong me ke kaumaha o 5 grams mai kahi kiʻekiʻe (g = 10 ms ^-2 ). Ke paʻi i ka papahele, ʻo ka wikiwiki o ka pōpō he 6 ms ^-1 a ma hope koke iho o ke paʻi ʻana i ka papahele, lele ka pōpō i luna me ka wikiwiki o 4 ms ^-1 . ʻO ka nui o ka impulse e hana ana ma ka pōpō he...

A. 0,50 Ns

B. 0,25 Ns

C. 0,10 Ns

D. 0,05 Ns

E. 0,01 Ns

Pahana

Ua ʻike ʻia :

Ka nuipa pōpō (m) = 5 grams = 0,005 kg

ʻO ka wikiwiki o ka pōpō ma mua pono o ke kuʻi ʻana i ka papahele (v _o ) = -6 m/s

ʻO ka wikiwiki o ka pōpō ma hope koke iho o ke kuʻi ʻana i ka papahele (vt ₎ = 4 m/s

ʻO ke ʻano o nā wikiwiki maikaʻi a me nā wikiwiki maikaʻi ʻole, ʻo ke kuhikuhi o ka wikiwiki o ka pōpō a i ʻole ke kuhikuhi o ka neʻe ʻana o ka pōpō ma mua o ke kuʻi ʻana he ʻokoʻa ia i ke kuhikuhi o ka neʻe ʻana o ka pōpō ma hope o ke kuʻi ʻana.

Nīnau ʻia : Impulse (I)

Pane :

ʻŌlelo ke kumumanaʻo impulse-momentum ua like ka impulse (I) me ka loli o ka momentum (Δp).

I = Δp = mv _t – mv _o = m (v _t – v _o )

ʻO I = (0,005)(4 – (-6)) = (0,005)(4 + 6) = (0,005)(10) = 0,05 Newton kekona

ʻO D ka pane pololei.

3. Ua kiola ʻia kahi pōpō 20-kalama me ka wikiwiki v ₁ = 4 ms ^-1 i ka hema. Ma hope o ke kuʻi ʻana i ka paia, lele ka pōpō me ka wikiwiki v ₂ = 2 ms ^-1 i ka ʻākau. ʻO ka impulse hopena….

A. 0,24 Ns

B. 0,12 Ns

C. 0,08 Ns

D. 0,06 Ns

E. 0,04 Ns

Pahana

Ua ʻike ʻia:

Ka nuipa pōpō (m) = 20 grams = 0,020 kg

ʻO ka wikiwiki o ka pōpō ma mua o ke kuʻi ʻana (v _o ) = -4 m/s (ma ka hema)

ʻO ka wikiwiki o ka pōpō ma hope o ke kuʻi ʻana (vt ₎ = +2 m/s (ma ka ʻākau)

Hāʻawi ʻia ʻo v _{o i kahi hōʻailona maikaʻi ʻole e hoʻokaʻawale i kona kuhikuhi mai v t}.

Nīnau ʻia: Impulse

Pane:

Impulse (I) = loli o ka momentum (Δp) = mvt _– mv _o

Ka Impulse (I) = m (vt _– v _o ) = 0,02 (2 – (-4))

Ka Impulse (I) = 0,02 (2 + 4) = 0,02 (6)

Impulse (I) = 0,12 Newton kekona.

ʻO ka pane pololei ʻo B.

4. Ua hoʻokuʻu ʻia kahi pōpō tenisi 100-gram i ka papahele mai ke kiʻekiʻe o 20 cm me ka ʻole o ka wikiwiki mua. Ma hope o ke kuʻi ʻana i ka papahele, lele ka pōpō me ka wikiwiki o 1 ms ^-1 a me (g = 10 ms ^-2 ). ʻO ka loli o ka momentum i ʻike ʻia e ka pōpō ʻo ia...

A. 0,1 Ns
B. 0,3 Ns
C. 0,5 Ns
D. 0,8 Ns
E. 0,9 Ns

Pahana
Ua ʻike ʻia :
Ka nuipa pōpō (m) = 100 grams = 0,1 kg
Kiʻekiʻe (h) = 20 kenimika = 0,2 mika
Ka wikiwiki ma muli o ke koʻikoʻi (g) = 10 m/s²
ʻO ka wikiwiki o ka pōpō ma hope koke iho o ke kuʻi ʻana i ka papahele (v)_t) = 1 m/s
Ua nīnau ʻia : ka loli o ka momentum o ka pōpō
Pane :
ʻO ka wikiwiki o ka pōpō ma mua o ka hopena (v)_o)
E helu i ka wikiwiki o ka pōpō ma mua o ka pā ʻana me ka hoʻohana ʻana i ke ʻano hāʻule manuahi. No ke kiʻekiʻe o ka hāʻule manuahi o ka pōpō (h) = 0,2 mika, ʻo ka wikiwiki ma muli o ke koʻikoʻi (g) = 10 m/s² a ua noi no ka wikiwiki o ka pōpō ke paʻi i ka papahele, no laila ua hoʻohana ʻia ke ʻano hana v² = 2 gh
v² = 2 (10)(0,2) = 4
v= √4 = -2 m/s
Hāʻawi ʻia kahi hōʻailona maikaʻi ʻole no ka mea ʻo ke kuhikuhi o ka neʻe ʻana o ka pōpō ma mua o ke kuʻi ʻana me ka papahele ua kūʻē i ke kuhikuhi o ka neʻe ʻana o ka pōpō ma hope o ke kuʻi ʻana me ka papahele.
Ka loli o ka momentum o ka pōpō (Δp)
Δp = mv_t – mv_o = m (v_t - v_o)
Δp = (0,1)(1 – (-2)) = (0,1)(1 + 2) = (0,1)(3) = 0,3 Newton kekona
ʻO ka pane pololei ʻo B.

Puna nīnau:

Nā Nīnau Hoʻokolohua Lahui no ke Kino no ke Kula Kiʻekiʻe/Kula Kiʻekiʻe ʻOihana