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slega [8]
2 years ago
7

Give 4 facts about the alkali metals

Physics
2 answers:
miss Akunina [59]2 years ago
8 0

Answer:

there very old

Explanation:

Korvikt [17]2 years ago
7 0

<u>Facts</u><u> </u><u>about</u><u> </u><u>alkali</u><u> </u><u>metals</u><u> </u><u>are</u><u>~</u>

  • Because they are so reactive with air and water, they are generally stored in oil.
  • Cesium clocks are considered the most accurate of all clocks.
  • highly reactive at standard temperature and pressure.
  • Sodium and potassium both play an important role in biological life on Earth.
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Solve for acceleration:

<em>a</em> = (21.4 m/s - 33.8 m/s) / (4.7 s)

<em>a</em> ≈ -2.6 m/s²

Solve for force:

<em>F</em> = (1400 kg) <em>a</em> ≈ -3700 N

The minus sign tells you the force points in the opposite direction of the car's motion. Its magnitude is always positive, so <em>F</em> = 3700 N.

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3 years ago
Unpolarized light with an average intensity of 845 W/m2 moves along the x-axis when it enters a Polarizer A with a vertical tran
horsena [70]

Answer:

θ = 36.2º

Explanation:

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The non-polarized light between the first polarized of this leaves half the intensity, with vertical polarization

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In this case, the incident light in the second polarizer has an intensity of I₁ = 422.5 W / m² and the light that passes through the polarizer has a value of

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      Cos θ = √ (275 / 422.5)

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