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:
increasing; speeding up is my answer
Answer:
1) 3.9 %
2) 1,38 kg
3) 0.13 cubic meters
Explanation:
Part 1)
Calculated current = 0.180 amps
Measured current: 0.173 amps
percent error : 
%
Part 2)
mass1 = 1,155 kg
mass2 = 0.22 kg
Addition; 1.155 + 0.22 = 1 375 kg which should be rounded to just two decimals according to the addition rules for uncertainties:
Answer : 1,38 kg
Part 3)
Volume = 0.885 x 0.20 x 0.75 cubic meters = 0.13275 cubic meters
Notice that the smallest number of significant figures among the set of dimension given is two. Therefore, our answer should be rounded to two significant figures. That is:
Volume = 0.13 cubic meters
Answer:
I go with D but what you can do is u can read each and choose the one that sounds right Hope this helps
