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777dan777 [17]
2 years ago
14

A disk of radius 25 cm spinning at a rate of 30 rpm slows to a stop over 3 seconds. what is the angular acceleration?

Physics
1 answer:
SCORPION-xisa [38]2 years ago
5 0

Answer:

α = -π/3 rad/s²

θ = 1.5π rad ≈ 4.71 rad

θ = 0.75 rev

Explanation:

30 rev/min (2π rad/rev) / (60 s/min) = π rad/s

α = (ωf - ωi) / t = (0 - π) / 3 = -π/3 rad/s²

θ = ½αt² = ½(π/3)3² = 1.5π rad ≈ 4.71 rad

θ = 1.5π rad / 2π rad/rev = 0.75 rev

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devlian [24]

Answer:

1) The speed of sound increases

2)  440 Hz

3)  29°C

4)  17°C

5) 434 Hz

6)  12 m/s

7)  17.3 m

Explanation:

1) The speed of sound increases

2) V = f×λ

f = V/λ = 343/0.78 = 439.744 ≈ 440 Hz

3) V = f×λ

512 × 0.68 = 348.16 m/s

348.16 - 331 = 17.16

T = 17.16/0.6 = 28.6 ≈ 29°C

4) Increase in speed = 350 - 340 = 10

Increase in temperature = 10/0.6 = 16.67° ≈ 17°C

5) f = V/λ = 343/0.79 = 434 Hz

6) 331 + 0.6×30 - (331 × 0.6 ×10) = 12 m/s

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3 years ago
How do you comprehend the fourth dimension?
sergij07 [2.7K]
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6 0
3 years ago
A protein molecule in an electrophoresis gel has a negative charge. The exact charge depends on the pH of the solution, but 30 e
Reika [66]

Answer:

7.401 * 10^(-15) N

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This means that force, F, is

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|F| = |-7401.24 * 10^(-18)|

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7 0
3 years ago
to determine the mass of the central object, we must apply newton's version of kepler's third law, which requires knowing the or
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The approximate orbital period of this star is 13 years.

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T² ∝ a³

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6 0
1 year ago
1. Strzała o masie 20 g tuż po wystrzale ma prędkość 50 m/s. Oblicz pracę wykonaną
kow [346]

Answer:

Explanation:

Question 1

An arrow weighing 20g shortly after firing has a speed of 50m / s. Calculate the work done by the athlete. What is the potential energy of the elasticity of the tensed string?

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A 80 kg athlete stood on a trampoline with a coefficient of elasticity of k = 2 kN / m. As far as the edge of the trampoline lowers.

force of elasticity

F = -kx

x = F / k

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F = mg

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F = 80kg * 10N / kg = 800 N

x = 800N / -2000N = -0.4

The trampoline will lower, so from the level by 0.4 meters and hence this minus

7 0
3 years ago
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