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
Answer:
Explanation:
Given
Distance to grandmother's house=100 mi
it is given that during return trip Julie spend equal time driving with speed 30 mph and 70 mph
Let Julie travel x mi with 30 mph and 100-x with 70 mph
x=30 mi
Therefore
Julie's Average speed on the way to Grandmother's house
=42 mph
On return trip
Answer:
Volcanic eruptions cool down the planet
Explanation:
Volcanic eruptions actually cool the planet because the particles ejected from volcanoes shade incoming solar radiation. ... The small ash and aerosol particles decrease the amount of sunlight reaching the surface of the Earth and lower average global temperatures.
Hope this helps!!! :D
To solve this problem we will use the basic concept given by the Volume of a sphere with which the atom approaches. The fraction in percentage terms would be given by the division of the total volume of the nucleus by that of the volume of the atom, that is,
Therefore the percent of the atom's volume is occupied by mass is 
SINGLE TO RIGHT OR CENTER FIELD-On a single to center or right field the first baseman will be the cutoff to home. The shortstop will cover second base.
