Answer:
Explanation:
Here image distance is fixed .
In the first case if v be image distance 
1 / v - 1 / -25 = 1 / .05 
1 / v = 1 / .05 - 1 / 25 
= 20 - .04 = 19.96 
v = .0501 m = 5.01 cm 
In the second case 
u = 4 , 
1 / v - 1 / - 4 = 1 / .05 
1 / v = 20 - 1 / 4 = 19.75 
 v = .0506 = 5.06 cm 
So lens must be moved forward by 5.06 - 5.01 =  .05 cm ( away from film )
 
        
             
        
        
        
Answer:
As you know, the denser objects have more weight per unit of volume, this will mean that the force that pulls down these objects is a bit larger.
This will mean that the denser objects will always go to the bottom.
This clearly implies that the red liquid, the one with one of the smaller densities, can not be at the bottom.
There are some cases where a liquid with a small density may become a lot denser as the temperature or pressure changes, and in a case like that, we could see the red liquid at the bottom, but for this case, there is no mention of changes in the temperature nor in the pressure, so this can be discarded.
The only thing that makes sense is that the red part at the bottom is the base of the tube, and has nothing to do with the red liquid.
 
        
             
        
        
        
Answer:
a)   S = 2.35 10³   J/m²2
,  
b)and the tape recorder must be in the positive Z-axis direction.
the answer is 5
c) the direction of the positive x axis
Explanation:
a) The Poynting vector or intensity of an electromagnetic wave is
           S = 1 /μ₀ E x B
if we use that the fields are in phase
           B = E / c
we substitute
          S = E² /μ₀ c
let's calculate
         s = 941 2 / (4π 10⁻⁷  3 10⁸)
         S = 2.35 10³   J/m²2
  
b) the two fields are perpendicular to each other and in the direction of propagation of the radiation
In this case, the electro field is in the y direction and the wave propagates in the ax direction, so the magnetic cap must be in the y-axis direction, and the tape recorder must be in the positive Z-axis direction.
the answer is 5
C) The poynting electrode has the direction of the electric field, by which or which should be in the direction of the positive x axis
 
        
             
        
        
        
<span>B.	a ship slowly sinking</span>
This is not balanced