Answer: 8.6 µm
Explanation:
At a long distance from the source, the components (the electric and magnetic fields) of the electromagnetic waves, behave like plane waves, so the equation for the y component of the electric field obeys an equation like this one:
Ey =Emax cos (kx-ωt)
So, we can write the following equality:
ω= 2.2 1014 rad/sec
The angular frequency and the linear frequency are related as follows:
f = ω/ 2π= 2.2 1014 / 2π (rad/sec) / rad = 0.35 1014 1/sec
In an electromagnetic wave propagating through vacuum, the speed of the wave is just the speed of light, c.
The wavelength, speed and frequency, are related by this equation:
λ = c/f
λ = 3.108 m/s / 0.35. 1014 1/s = 8.6 µm.
Answer:
33333.35 kg
Explanation:
I got it right on Acellus, rounded to 33300 sigfigs
When Alana moving 19km/h, a stationary object will be perceived by her as moving toward her with 19km/h velocity. If the object is not stationary(velocity isn't zero), the speed will increase by the object velocity.
the relative speed of the tennis ball=
the speed of Alana + true speed of the tennis ball
19km/h+ 11km/h= 30km/h
Answer:
Approximately 
.
Explanation:
This question suggests that the rotation of this object slows down "uniformly". Therefore, the angular acceleration of this object should be constant and smaller than zero.
This question does not provide any information about the time required for the rotation of this object to come to a stop. In linear motions with a constant acceleration, there's an SUVAT equation that does not involve time:
,
where
is the final velocity of the moving object, 
is the initial velocity of the moving object,
is the (linear) acceleration of the moving object, and
is the (linear) displacement of the object while its velocity changed from to .
The angular analogue of that equation will be:
, where
and 
are the initial and final angular velocity of the rotating object,
is the angular acceleration of the moving object, and
is the angular displacement of the object while its angular velocity changed from to .
For this object:
, whereas
.
The question is asking for an angular acceleration with the unit 
. However, the angular displacement from the question is described with the number of revolutions. Convert that to radians:
.
Rearrange the equation and solve for :
.
-- all electrons are identical
-- electrons have a negative electrical charge
-- the size of the charge is equal to the positive charge on a proton
-- but it takes about 1,840 electrons to make the mass of one proton
