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2 years ago

4. How long does it take a car traveling at 45 km/h to travel 100.0 m? 4500m

Physics

1 answer:

Trava [24]2 years ago

8 0

Answer:

8.0s

Explanation:

45 km/h ÷ 3.6 = 12.5 m/s

t.v = d/t

vt/v = d/v

t = d/v = 100.0m /12.5 m/s = 8.0s

Hope this helps!!

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Answer:

The correct answer is b, x = 9 cos (pi / 2 t)

Explanation:

The equation that describes a simple pendulum is

θ = θ₀ cos (wt + φ)

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We replace

d / L = x₀ / L cos (wt + φ)

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We replace

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Angular velocity is related to frequency and period.

w = 2π f = 2π / T

The period is the time of a complete oscillation T = 4 s

w =2π / 4

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Let's replace

x = 9 cos (π/2 t + φ)

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x = 9 cos (pi / 2 t)

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Explanation:

It is given that,

Mass of the brick, m = 1.15 kg

Radius of the circle, r = 1.44 m

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DE = K₁ - K₂ = 86,500 lbs. mi² / hr²

This loss is due to the impact, and is represented by the work done by friction forces (internal) during the impact.

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