C and D are units of length or distance.
A is a measured angle.
B is a unit of angular measurement.
Answer:
law of action and riactiond
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[D. 2 protons, 2 electrons, and 1 neutron.]
As we know that, protons are embedded in the nucleus with neutron having no charge. So, nucleus has positive charge. Electrons are revolved around the nucleus of the atom. Proton has positive charge and electron has negative charge.
Number of proton = Number of electron.
Hence, both 2 protons and 2 electrons make the atom electrically neutral. So, the net charge of atom is 0. Neutron are the subatomic particle which has only mass.
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Answer:
1 eV
Explanation:
Given:
Work function, ∅ = 2.00 eV
Kinetic energy of the ejected of the electron, K.E = 4.0 eV
Now,
using the photoelectric equation
, we have
Energy of the photon (E) = ∅ + K.E
also,
E = hc/λ
where, h is plank's constant
c is the speed of the light
λ is the wavelength
thus, we have
hc/λ = 2 + 4 = 6 eV
Energy of photon = 6eV
Now,
for the second case
λ' = 2λ
when Wavelength is doubled , E is halved
thus,
E' = hc/λ'
or
E' = hc/2λ
or
E' = E/2 = 6/2 = 3 eV
also,
E' = ∅ + KE
'
thus on substituting the values,
3 = 2 + KE'
or
KE' = 1 eV
Hence, the maximum kinetic energy for the second case is 1 eV
The speed of the man and the chair after the book is thrown is 0.2 m/s.
The given parameters:
- <em>mass of the book, m₁ = 2.1 kg</em>
- <em>speed of the book, u₁ = 7.2 m/s</em>
- <em>mass of the man, M = 70 kg</em>
- <em>mass of the book, m = 9.2 kg</em>
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The total mass of the man and the book is calculated as follows;
m₂ = 70 kg + 9.2 kg
m₂ = 79.2 kg
The speed of the man and the chair after the book is thrown is determined by applying the principle of conservation of linear momentum;

Thus, the speed of the man and the chair after the book is thrown is 0.2 m/s.
Learn more about conservation of linear momentum here: brainly.com/question/7538238