Protons and neutrons have similar mass
Electrons are smaller then a proton or a neutron
Answer:
Explanation:
Mass of a proton,
Mass of an electron,
The distance between the electron and the proton is,
We need to find the mutual attractive gravitational force between the electron and proton. The gravitational force is given by :
Where G is the universal Gravitational constant
So, the force between the electron and proton is .
By Newton's second law, the net vertical force acting on the object is 0, so that
<em>n</em> - <em>w</em> = 0
where <em>n</em> = magnitude of the normal force of the surface pushing up on the object, and <em>w</em> = weight of the object. Hence <em>n</em> = <em>w</em> = <em>mg</em> = 196 N, where <em>m</em> = 20 kg and <em>g</em> = 9.80 m/s².
The force of static friction exerts up to 80 N on the object, since that's the minimum required force needed to get it moving, which means the coefficient of <u>static</u> friction <em>µ</em> is such that
80 N = <em>µ</em> (196 N) → <em>µ</em> = (80 N)/(196 N) ≈ 0.408
Moving at constant speed, there is a kinetic friction force of 40 N opposing the object's motion, so that the coefficient of <u>kinetic</u> friction <em>ν</em> is
40 N = <em>ν</em> (196 N) → <em>ν</em> = (40 N)/(196 N) ≈ 0.204
And so the closest answer is C.
(Note: <em>µ</em> and <em>ν</em> are the Greek letters mu and nu)
Answer:
c = 1 / √(ε₀*μ₀)
Explanation:
The speed of the electromagnetic wave in free space is given in terms of the permeability and the permittivity of free space by
c = 1 / √(ε₀*μ₀)
where the permeability of free space (μ₀) is a physical constant used often in electromagnetism and ε₀ is the permittivity of free space (a physical constant).
Answer:
Max speed =
Max acceleration =
Explanation:
Given the description of period and amplitude, the SHM could be described by:
and its angular velocity can be calculated doing the derivative:
And therefore, the tangential velocity is calculated by multiplying this expression times the radius of the movement (3 m):
and is given in m/s.
Then the maximum speed is obtained when the cosine function becomes "1", and that gives:
Max speed =
The acceleration is found from the derivative of the velocity expression, and therefore given by:
and the maximum of the function will be obtained when the sine expression becomes "-1", which will render:
Max acceleration =