Answer:
Explanation:18kt alloy contains
i) 75% of gold
rhogold=19.3g/cm^3
=75/100×19.3
=14.475g/cm^3
ii) 16% of silver
rhosilver=10.5g/cm^3
=16/100×10.5
=1.68g/cm^3
iii) 9% of copper
rhocopper =8.90g/cm^3
=9/100×8.9
=0.801g/cm^3
Overall density of 18kt gold
=(0.801+1.68+14.475)g/cm^3
=16.956g/cm^3
=17g/cm^3 to 3s.f
 
        
             
        
        
        
Answer:
a
     
b
    
Explanation:
From the question we are told that 
      Their distance apart is  
       The  wavelength of each source wave 
Let the distance from source A  where the construct interference occurred be z 
Generally the path difference for constructive interference is 
               
Now given that we are considering just the straight line (i.e  points along the line connecting the two sources ) then the order of the maxima m =  0 
   so 
         
=>     
=>     
Generally the path difference for destructive  interference is 
            
=>         
=>        
substituting values 
           
 =>      
So  
       
       
and 
       
 =>   
=>    
 
        
             
        
        
        
The phenomenon of inducing voltage by changing the magnetic field around a conductor will be Electromagnetic Induction. Option B is correct.
<h3>What is the Faraday law of electromagnetic induction?</h3>
According to Faraday's law of electromagnetic induction, the rate of change of magnetic flux link with the coil is responsible for generating emf in the coil to result in the flow of amount of current .
So in order to increase the current, we need to increase the EMF;
so we can increase it by;
1) Increasing the number of turns
2) Increase the area of the loop
3) By moving the magnet faster
Hence, option B is correct.
To learn more about Faraday law of electromagnetic induction:
brainly.com/question/13369951
#SPJ1
 
        
             
        
        
        
Answer:
1069.38 gallons
Explanation:
Let V₀ = 1.07 × 10³ be the initial volume of the gasoline at temperature θ₁ = 52 °F. Let V₁ be the volume at θ₂ = 97 °F. 
V₁ = V₀(1 + βΔθ)  β = coefficient of volume expansion for gasoline = 9.6 × 10⁻⁴ °C⁻¹
Δθ = (5/9)(97°F -52°F) °C = 25 °C.
Let V₂ be its final volume when it cools to 52°F in the tank is 
V₂ = V₁(1 - βΔθ) = V₀(1 + βΔθ)(1 - βΔθ) = V₀(1 - [βΔθ]²) 
     = 1.07 × 10³(1 - [9.6 × 10⁻⁴ °C⁻¹ × 25 °C]²)
     = 1.07 × 10³(1 - [0.024]²)
     =  1.07 × 10³(1 - 0.000576)
     = 1.07 × 10³(0.999424)
     = 1069.38 gallons