Answer:
Electric potential, E = 2100 volts
Explanation:
Given that,
Electric field, E = 3000 N/C
We need to find the electric potential at a point 0.7 m above the surface, d = 0.7 m
The electric potential is given by :
V = 2100 volts
So, the electric potential at a point 0.7 m above the surface is 2100 volts. Hence, this is the required solution.
Answer: a) 274.34 nm; b) 1.74 eV c) 1.74 V
Explanation: In order to solve this problem we have to consider the energy balance for the photoelectric effect on tungsten:
h*ν = Ek+W ; where h is the Planck constant, ek the kinetic energy of electrons and W the work funcion of the metal catode.
In order to calculate the cutoff wavelength we have to consider that Ek=0
in this case h*ν=W
(h*c)/λ=4.52 eV
λ= (h*c)/4.52 eV
λ= (1240 eV*nm)/(4.52 eV)=274.34 nm
From this h*ν = Ek+W; we can calculate the kinetic energy for a radiation wavelength of 198 nm
then we have
(h*c)/(λ)-W= Ek
Ek=(1240 eV*nm)/(198 nm)-4.52 eV=1.74 eV
Finally, if we want to stop these electrons we have to applied a stop potental equal to 1.74 V . At this potential the photo-current drop to zero. This potential is lower to the catode, so this acts to slow down the ejected electrons from the catode.
Question 2 is because the passengers have inertia, which is a tendency to resist change in motion
Answer:
Velocity
Explanation:
Velocity is an object's change in motion per unit time in a specified direction
Answer:
The Apollo program or Project Apollo was a series of human spaceflight missions undertaken by the u.S. Devoted to the goal of landing a man on the moon and returning him to earth safely.
Explanation:
Project Apollo or Apollo program was the spaceflight program carried out by the United States of America during the years 1961-1972 using the Apollo spacecraft. This project's main goal was to land a man on the Moon and to safely return him to Earth. This goal was accomplished with the Apollo 11 moon-landing mission on July 20, 1969, when an Apollo Lunar Module (LM) landed on the Moon's surface and the astronauts Neil Armstrong and Buzz Aldrin walked on the lunar surface while Michael Collins stayed in the command and service module (CSM) in the lunar orbit. On July 24, all three astronauts landed safely on Earth.
This project included three unmanned test flights (Apollo 4 through Apollo 6) and eleven manned flights (Apollo 7 through Apollo 17). All these spaceflight missions were carried out by NASA (National Aeronautics and Space Administration) and all were launched from the Kennedy Space Center, Florida.
