Physics, 03.03.2020 21:57 azireyathurmond1
A beam of electrons is accelerated from rest through a potential difference of 0.200 kV and then passes through a thin slit. When viewed far from the slit, the diffracted beam shows its first diffraction minima at ± 13.6 ∘ from the original direction of the beam.
Do we need to use relativity formulas? Select the correct answer and explanation.
a. No. The electrons gain kinetic energy K as they are accelerated through a potential difference V, so Ve=K=mc2/(γ−1). The potential difference is 0.200 kV , soVe= 0.200 keV. Solving for γ and using the fact that the rest energy of an electron is0.511 MeV, we have γ–1=(0.511MeV)/(0.200keV) so γ−1>>1 which means that we do not have to use special relativity.
b. Yes. The electrons gain kinetic energy K as they are accelerated through a potential difference V, so Ve=K=(γ−1)mc2. The potential difference is 0.200 kV , soVe= 0.200 keV. Solving for γ and using the fact that the rest energy of an electron is0.511 MeV, we have γ–1=(0.200keV)/(0.511MeV) so γ<<1 which means that we have to use special relativity.
c. Yes. The electrons gain kinetic energy K as they are accelerated through a potential difference V, so Ve=K=mc2/(γ−1). The potential difference is 0.200 kV , soVe= 0.200 keV. Solving for γ and using the fact that the rest energy of an electron is0.511 MeV, we have γ–1=(0.511MeV)/(0.200keV) so γ>>1 which means that we have to use special relativity.
d. No. The electrons gain kinetic energy K as they are accelerated through a potential difference V, so Ve=K=(γ−1)mc2. The potential difference is 0.200 kV , soVe= 0.200 keV. Solving for γ and using the fact that the rest energy of an electron is 0.511 MeV, we have γ–1=(0.200keV)/(0.511MeV) so γ−1<<1 which means that we do not have to use special relativity.
Part B
How wide is the slit?
Answers: 2
Physics, 22.06.2019 12:00
The sun’s mass is 2.0×10^ 30 kg, its radius is 7.0×10 5 km, and it has a rotational period of approximately 28 days. if the sun should collapse into a white dwarf of radius 3.5×10 3 km, what would its period be if no mass were ejected and a sphere of uniform density can model the sun both before and after?
Answers: 3
Physics, 22.06.2019 18:10
Which of the following statement is false ? a.batteries should never be stored on metal trays or outside in the elements)b, battery acid cannot be neutralized)c.do not stack batteries on top of each other)d.never put a damaged battery in a dumpster. i
Answers: 1
Physics, 22.06.2019 18:50
8.29 two streams containing pyridine and acetic acid at 25°c are mixed and fed into a heat exchanger. due to the heat-of-mixing effect, it is desired to reduce the temperature after mixing to 25°c using a stream of chilled ethylene glycol as indicated in the diagram. calculate the mass flow rate of ethylene glycol needed. the heat capacity of ethylene glycol at these conditions is approximately 2.8 kj/(kg k), and the enthalpy change of mixing (δmixh) is given below.
Answers: 3
Physics, 22.06.2019 22:30
Use the drop-down menus to answer each question. which line represents the movement of a cart with a constant acceleration? a which line represents the movement of a cart with a constant velocity? c which lines represents a cart with no velocity or acceleration? b
Answers: 1
A beam of electrons is accelerated from rest through a potential difference of 0.200 kV and then pas...
Physics, 26.10.2021 19:30
History, 26.10.2021 19:30
Mathematics, 26.10.2021 19:30
Mathematics, 26.10.2021 19:30
History, 26.10.2021 19:30
Mathematics, 26.10.2021 19:30
Computers and Technology, 26.10.2021 19:30