Answer:
Lithium
Explanation:
The equation for the photoelectric effect is

where
is the energy of the incident photon, with
h being the Planck constant
c is the speed of light
is the wavelength of the photon
is the work function of the metal (the minimum energy needed to extract the photoelectron from the metal)
is the maximum kinetic energy of the emitted photoelectrons
In this problem, we have
is the wavelength of the incident photon
is the maximum kinetic energy of the electrons
First of all we can find the energy of the incident photon

Converting into electronvolts,

So now we can re-arrange the equation of the photoelectric effect to find the work function of the metal

So the metal is most likely Lithium, which has a work function of 2.5 eV.
Answer: Part A the right sentence is: Because the proton is a positive charge and it slows down as it travels, it must be moving from a region of lower potential to a region of higher potential
Part B. aproximatelly 98 times ΔV V
Part C. the initial kinetic energy of the proton is 1.87 10^3 eV
Explanation: Part A. The field stops the proton so the lines of electric fild must be directed in opposite direction of its movement. This means that the proton moves to a higher potential. Part B The kinetic energy of the is transformed in electric potenctial for the proton.
Part C. Energy in J divide the charge of electron gives the energy in eV.
( 3 yr) · (186,282.397 mile/s) · (86,400 s/day) · (365 day/yr)
= (3 · 186,282.397 · 86,400 · 365) mile
= 1.762380502 x 10¹³ miles
= 1.8 x 10¹³ miles (rounded to the nearest trillion miles)
Answer:
0.98kW
Explanation:
The conservation of energy is given by the following equation,


Where
Mass flow
Specific Enthalpy (IN)
Specific Enthalpy (OUT)
Gravity
Heigth state (In, OUT)
Velocity (In, Out)
Our values are given by,




For this problem we know that as pressure, temperature as velocity remains constant, then


Then we have that our equation now is,


