Cov khoom me me hauv qhov sib npaug ob-seem - kev siv cov teeb meem thiab kev daws teeb meem ntawm Newton txoj cai thawj zaug

1. Nrhiav lub zog nruj T₁, T₂, thiab T₃Tsis quav ntsej txog cov hlua loj.

tshuaj

(a) Daim duab qhia txog lub cev dawb rau yam khoom (b) Daim duab qhia txog lub cev dawb rau txoj hlua

Thov cov Txoj cai lij choj thawj zaug ntawm Newton rau ntawm qhov khoom:

ΣF_y = 0

T₁ – w = 0

T₁ = w = mg

T₁ = (5 kg)(9.8 m/s)²)

T₁ = 49 kg m/s²

T₁ = 49 N

Siv Newton txoj cai thawj zaug rau ntawm txoj hlua:

∑F_x = 0

T_3x - T _2x = 0

T₃ coj 30^o - T₂ coj 40^o = 0

0.87 T₃ – 0.77 T₂ = 0

0.87 T₃ = 0.77 T₂

T₂ = 0.87 T₃ / 0.77 = 1.1 T₃ ———- Kab zauv 1

-

∑F_y = 0

T_3y +T_2y - T_1y = 0

T₃ kev txhaum 30^o +T₂ kev txhaum 40^o - T₁ = 0

0.5 T₃ + 0.64 T₂ – 49 N = 0 ———- Kab zauv 2

Hloov T₂ hauv kab zauv 2 rau hauv kab zauv 2:

0.5 T₃ + 0.64 (1.1 T)₃) – 49 N = 0

0.5 T₃ + 0.70 T₃ - 49 = 0

1.2 T₃ - 49 = 0

1.2 T₃ = 49

T₃ = 49/1.2

T₃ = 41 N

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T₂ = 1.1 T₃

T₂ = (1.1)(40.8 N)

T₂ = 45 N

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1. Cov khoom me me hauv ib qho kev sib npaug
2. Cov khoom me me hauv qhov sib npaug ob sab
3. Kev sib npaug ntawm lub cev txuas nrog los ntawm cov hlua thiab pulleys
4. Kev sib npaug ntawm lub cev ntawm lub dav hlau inclined