Answer:
P₂ = 2 P₁
we conclude that in the second time the power used is double that in the first rise
Explanation:
In this exercise we are asked the power to climb the stairs, if we assume that we go up with constant speed, we use an energy equal to the potential energy due to the difference in height of the stairs, as this height is constant the potential energy does not change and therefore therefore the energy used by us does not change either.
Now we can analyze the required power,
P = W / t
From the analysis of the previous paragraph the work is equal to the energy used, according to the work energy theorem,
therefore the first time the power is
P₁ = E / 10
P₁ = 0.1 E
for the second time the power is
P₂ = E / 5
P₂ = 0.2 E
we see that the power in the second case is
P₂ = 2 P₁
Therefore, we conclude that in the second time the power used is double that in the first rise.
The answer is elliptical orbits. Here is are my reason for thinking it is what I know it is. All planets move in elliptical orbits, with the sun at one focus. This is one of Kepler's laws. The elliptical shape of the orbit is a result of the inverse square force of gravity. The eccentricity of the ellipse is greatly exaggerated here.
Answer:. Option c
Explanation: the speed of an electromagnetic wave is simply the vector product of the magnetic field and the electric field.
The direction of the velocity is the direction of the electromagnetic wave.
The wave is already moving towards the negative y axis (-j) and the magnetic field is already pointing towards the positive x axis (i)
From cross product of unit vectors
i × j = k
i × k = - j
With the second identity, we can see that the electric field will be pointing towards the positive of the x axis (k).
Option c is validated
Incomplete question. Full text is:
"<span>Give an example of a situation in which you would describe an object's position in (a) one-dimension coordinates (b) two-dimension coordinates (c) three-dimension coordinates"
Solution
(a) One dimension example: a man walking along a metal plank. We just need to specify one coordinate, the distance from the beginning of the plank.
(b) Two-dimension example: a ball moving on a circle. In this case, we need two coordinates: (x,y) to specify the position of the ball at every instant, since it is moving on a 2-D plane.
(c) The position of an airplane in the air: in this case we need 3 coordinates, the height, the latitude and the longitude of the airplane.</span>
Answer:
Explanation:
THE GIVEN sheet can be taken as two horizontal force with surface charge density is
at one surface is ∈_1 = 
at oher surface is ∈_2= 
the magnitude of electric field due to surface charge is given as
So, electric field at P (2 CM below from surface is) = E_1 +E_2
