Answer:
Europium has a bright shiny surface. it's steel grey and has a melting point of 826 degree Celsius and a boiling point of about 1,489 degree Celsius.
Explanation:
the density is 5.24 grams per cubic centimeter.
Answer:
Ф = 2.179 eV
Explanation:
This exercise has electrons ejected from a metal, which is why it is an exercise on the photoelectric effect, which is explained assuming the existence of energy quanta called photons that behave like particles.
E = K + Ф
the energy of the photons is given by the Planck relation
E = h f
we substitute
h f = K + Ф
Ф= hf - K
the speed of light is related to wavelength and frequency
c = λ f
f = c /λ
Φ =
let's reduce the energy to the SI system
K = 0.890 eV (1.6 10⁻¹⁹ J / 1eV) = 1.424 10⁻¹⁹ J
calculate
Ф = 6.63 10⁻³⁴ 3 10⁸/405 10⁻⁹ -1.424 10⁻¹⁹
Ф = 4.911 10⁻¹⁹ - 1.424 10⁻¹⁹
Ф = 3.4571 10⁻¹⁹ J
we reduce to eV
Ф = 3.4871 10⁻¹⁹ J (1 eV / 1.6 10⁻¹⁹ J)
Ф = 2.179 eV
As per bernoulli's principle
here
= pressure upwards
= pressure downwards
= velocity of air upwards
= velocity of air downwards
now from this equation we can say that the pressure difference will be
now the force due to this pressure difference will be
so this is the above force which is given above
It is also known as iteration. It is used mostly in computer programming with for and for each loops in which iteration is present. In mathematics there are some "interational operations" like product and sum for eg:
The above equation describes the summation of J alike variables n times.