<span>This is best understood with Newtons Third Law of Motion: for every action there is an equal and opposite reaction. That should allow you to see the answer.</span>
        
             
        
        
        
D. to be structural material
        
                    
             
        
        
        
 <span>
The needle of a compass will always lies along the magnetic
field lines of the earth. 
A magnetic declination at a point on the earth’s surface
equal to zero implies that 
the horizontal component of the earth’s magnetic field line
at that specific point lies along 
the line of the north-south magnetic poles. </span>
The presence of a
current-carrying wire creates an additional <span>
magnetic field that combines with the earth’s magnetic field.
Since magnetic 
<span>fields are vector quantities, therefore the magnetic field of
the earth and the magnetic field of the vertical wire must be
combined vectorially. </span></span>
<span>
Where:</span>
B1 = magnetic field of
the earth along the x-axis = 0.45 × 10 ⁻ ⁴ T 
B2 = magnetic field due to
the straight vertical wire along the y-axis 
We can calculate for B2
using Amperes Law:
B2 = μ₀ i / [ 2 π R ] 
B2 = [ 4π × 10 ⁻ ⁷ T • m / A ] ( 36 A ) / [ 2 π (0.21 m ) ] <span>
B2 = 5.97 × 10 ⁻ ⁵ T = 0.60 × 10 ⁻ ⁴ T </span>
The angle can be
calculated using tan function:<span>
tan θ = y / x = B₂ / B₁ = 0.60 × 10 ⁻ ⁴ T / 0.45 × 10 ⁻ ⁴ T <span>
tan θ = 1.326</span></span>
θ = 53°
<span>
<span>The compass needle points along the direction of 53° west of
north.</span></span>
 
        
             
        
        
        
Answer:
The angular magnification is 
Explanation:
From the question we are told 
            The focal length is  
           The near point is 
The angular magnification is mathematically represented as 
                           
Substituting values 
                         
                            