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Shkiper50 [21]
2 years ago
15

Một người đi xe đạp trong 40 phút với vận tốc là 12km/h. Hỏi quãng đường đi được là bao nhiêu?

Physics
1 answer:
Karo-lina-s [1.5K]2 years ago
3 0

Answer:

khoảng cách = 8km / h

Explanation:

khoảng cách = tốc độ / thời gian

khoảng cách = 12/40

khoảng cách = 8km / h

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We use the formula, to calculate the volume of water displaced by concrete canoe,

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So,

V =\frac{ 147\ lb}{62.4\ lb/ft^3}=2.356\ ft^3.

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v=\frac{38\ lb}{62.4\ lb/ft^3} =0.6089\ ft^3

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3 years ago
Sam, whose mass is 78 kg , stands at the top of a 11-m-high, 110-m-long snow-covered slope. His skis have a coefficient of kinet
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Answer:

v = 8.09   m/s

Explanation:

For this exercise we use that the work done by the friction force plus the potential energy equals the change in the body's energy.

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Axis y

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X axis

        Wₓ - fr = ma

let's use trigonometry

        sin  θ = y / L

         sin θ = 11/110 = 0.1

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         cos 5.74 = W_y / W

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         W_fr = - μ W L cos θ  

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let's calculate

        v² = 2 9.8 11 - 2 0.07 9.8 110 cos 5.74

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