Answer:
C) True. At maximum displacement, its instantaneous velocity is zero.
Explanation:
The simple harmonic movement is given by
x = A cos wt
Speed
v = - A w sin wt
At the point of maximum displacement x = A
A = A cos wt
cos wt = 1
wt = 0
We replace the speed
v = -Aw sin 0 = A w
Speed is maximum
Let's review the claims
A) False. Speed is zero
B) False. It can be determined
C) True. Agree with our result
D) False. When one is maximum the other is minimum
The air resistance on the feather would be the correct answer.
Answer:
a) True. The number of photoelectrons is proportional to the amount (intensity) of the incident beam. From the expression above we see that threshold frequency cannot emit electrons.
b) λ = c / f
Therefore, as the wavelength increases, the frequency decreases and therefore the energy of the photoelectrons emitted,
c) threshold energy
h f =Ф
Explanation:
It's photoelectric effect was fully explained by Einstein by the expression
Knox = h f - fi
Where K is the kinetic energy of the photoelectrons, f the frequency of the incident radiation and fi the work function of the metal
a) True. The number of photoelectrons is proportional to the amount (intensity) of the incident beam. From the expression above we see that threshold frequency cannot emit electrons.
b) wavelength is related to frequency
λ = c / f
Therefore, as the wavelength increases, the frequency decreases and therefore the energy of the photoelectrons emitted, so there is a wavelength from which electrons cannot be removed from the metal.
c) As the work increases, more frequency radiation is needed to remove the electrons, because there is a threshold energy
h f =Ф
Answer:
The speed of space station floor is 49.49 m/s.
Explanation:
Given that,
Mass of astronaut = 56 kg
Radius = 250 m
We need to calculate the speed of space station floor
Using centripetal force and newton's second law
Where, v = speed of space station floor
r = radius
g = acceleration due to gravity
Put the value into the formula
Hence, The speed of space station floor is 49.49 m/s.
