It applies to both physical and chemical changes.
Answer:
frequency = 8.22 x 10¹⁴ s⁻¹
Explanation:
An electron's positional potential energy while in a given principle quantum energy level is given by Eₙ = - A/n² and A = constant = 2.18 x 10⁻¹⁸j. So to remove an electron from the valence level of Boron (₅B), energy need be added to promote the electron from n = 2 to n = ∞. That is, ΔE(ionization) = E(n=∞) - E(n=2) = (-A/(∞)²) - (-A/(2)²) = [2.18 x 10⁻¹⁸j/4] joules = 5.45 x 10⁻¹⁹ joules.
The frequency (f) of the wave ionization energy can then be determined from the expression ΔE(izn) = h·f; h = Planck's Constant = 6.63 x 10⁻³⁴j·s. That is:
ΔE(izn) = h·f => f = ΔE(izn)/h = 5.45 x 10⁻¹⁹ j/6.63 x 10⁻³⁴ j·s = 8.22 x 10¹⁴ s⁻¹
<span>If a lever has a constant force applied at 90∘ to the lever arm at a fixed distance from the pivot point (point of rotation), the torque on the lever is given by Torque = force (at 90∘ to lever arm) × distance to pivot point
Force should be perpendicular to the lever arm
Therefore; you would do 15N X 2.0 m = 30 Nm or 30Joules</span>
The Density of the metal is 5.6 g/cm³
<h3>What is the density of a substance?</h3>
The density of a substance is the ratio of the mass and the volume of the substance.
The density of the metal is calculated as follows:
mass of metal = 1.4 kg = 1400 g
volume of metal = 3.2 * 17.1 * 4.6 = 251.712 cm³
Density of metal = 1400 g/251.712 cm³
Density of the metal = 5.6 g/cm³
Therefore, the density of the metal is obtained from the mass and the volume of the metal.
Learn more about density at: brainly.com/question/1354972
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Answer:
mitosis
Explanation:
because ur a cumt who doesn't know the answer
