I attached the full question.
We know that for a parallel-plate capacitor the surface charge density is given by the following formula:
![\sigma=\varepsilon_0 \frac{V}{d}](https://tex.z-dn.net/?f=%5Csigma%3D%5Cvarepsilon_0%20%5Cfrac%7BV%7D%7Bd%7D)
Where V is the voltage between the plates and d is separation.
Voltage is by definition:
![V=Ed](https://tex.z-dn.net/?f=V%3DEd)
Voltage is analog to the mechanical work done by the force.
Above formula is correct only If the field is constant, and we can assume that it is since no function has been given.
The charge density would then be:
![\sigma=\varepsilon_0 \frac{Ed}{d}=\varepsilon_0E\\ \sigma= 8.85\cdot10^{-12}\cdot 2.1\cdot 10^6= 0.0000185\frac{c}{m^2}](https://tex.z-dn.net/?f=%5Csigma%3D%5Cvarepsilon_0%20%5Cfrac%7BEd%7D%7Bd%7D%3D%5Cvarepsilon_0E%5C%5C%0A%5Csigma%3D%208.85%5Ccdot10%5E%7B-12%7D%5Ccdot%202.1%5Ccdot%2010%5E6%3D%200.0000185%5Cfrac%7Bc%7D%7Bm%5E2%7D)
Please note that elecric permittivity of air is very close to elecric permittivity of vacum, it is common to use them <span>interchangeably</span>.
We know that momentum = mass times velocity
So a. 720 kgm/s
Given Information:
Pendulum 1 mass = m₁ = 0.2 kg
Pendulum 2 mass = m₂ = 0.6 kg
Pendulum 1 length = L₁ = 5 m
Pendulum 2 length = L₂ = 1 m
Required Information:
Affect of mass on the frequency of the pendulum = ?
Answer:
The mass of the ball will not affect the frequency of the pendulum.
Explanation:
The relation between period and frequency of pendulum is given by
f = 1/T
The period of pendulum is given by
T = 2π√(L/g)
Where g is the acceleration due to gravity and L is the length of the string
As you can see the period (and frequency too) of pendulum is independent of the mass of the pendulum. Therefore, the mass of the ball will not affect the frequency of the pendulum.
Bonus:
Pendulum 1:
T₁ = 2π√(L₁/g)
T₁ = 2π√(5/9.8)
T₁ = 4.49 s
f₁ = 1/T₁
f₁ = 1/4.49
f₁ = 0.22 Hz
Pendulum 2:
T₂ = 2π√(L₂/g)
T₂ = 2π√(1/9.8)
T₂ = 2.0 s
f₂ = 1/T₂
f₂ = 1/2.0
f₂ = 0.5 Hz
So we can conclude that the higher length of the string increases the period of the pendulum and decreases the frequency of the pendulum.
I know that protons and neutrons are located at the center of an atom, so the correct answer is D