Answer:
 r₂ = 0.316 m
Explanation:
The sound level is expressed in decibels, therefore let's find the intensity for the new location
             β = 10 log  
let's write this expression for our case
            β₁ = 10 log \frac{I_1}{I_o}
            β₂ = 10 log \frac{I_2}{I_o}
            
           β₂ -β₁ = 10 (  )
)
           β₂ - β₁ = 10  
           log \frac{I_2}{I_1} =  = 3
 = 3
             = 10³
 = 10³
            I₂ = 10³ I₁
having the relationship between the intensities, we can use the definition of intensity which is the power per unit area
            I = P / A
            P = I A
the area is of a sphere
           A = 4π r²
            
the power of the sound does not change, so we can write it for the two points
           P =  I₁ A₁ =  I₂ A₂
           I₁ r₁² = I₂ r₂²
we substitute the ratio of intensities
           I₁ r₁² = (10³ I₁ ) r₂²
          r₁² = 10³ r₂²
          
          r₂ = r₁ / √10³
          
we calculate
           r₂ =  
           r₂ = 0.316 m
 
        
             
        
        
        
Answer:
The answer is 631.157
Explanation:
The question requested that the answer to the subtraction of 26.543 from 657.70 must be written using significant figures.
Here are a few tips about how to Identify significant figures.
1) It should be noted that <u>the number "0" is what is usually (but not always) affected</u> while trying to identify significant figures. Hence, <u>all other numbers/digits are always significant</u>. For example, 26.543 has five significant figures.
2) The zeros found between these "other numbers/digits" are also significant. For example, 2202 has four significant figures.
3) In the case of a decimal, the tailing zeros or the final zero is also significant. 657.70 and 657.07 have five significant figures.
Now, back to the question
657.70  - 26.543  = 631.157.
Our final answer does not have a zero, hence all the digits (six) are significant.
 
        
             
        
        
        
Answer:
Explanation:
 We shall consider direction towards left as positive Let the required velocity be v and let v makes an angle φ 
 Applying law of conservation of momentum along direction of original motion 
m₁ v₁  - m₂ v₂ = m₂v₃ - m₁ v₄
0.132 x 1.25 - .143 x 1.14 = 1.03 cos43 x .143 - v cos θ
v cos θ = .8 
 Applying law of conservation of momentum along direction perpendicular to direction of original motion 
1.03 sin 43 x .143 = .132 x v sinθ
v sinθ = .76 
squaring and adding 
v² = .76 ² + .8²
v = 1.1 m /s
Tan θ = .76 / .8
θ = 44° 
 
        
             
        
        
        
Carbon isn’t because all the others on the list are naturally made apart from carbon which is man made because of all the pollution . X
        
             
        
        
        
Answer:
t = 13.7 s or t = 14 s with proper significant figures
Explanation:
The initial speed is 0 m/s since the car starts from rest, acceleration is 5.5 m/s2 and distance is 523 m. 
Since we have initial speed, acceleration and distance we can use the following formula to find the time. We can now use algebra to work out our answer.
d = vt +  at²
at² 
523 = (0)t + ( )(5.5)t²
)(5.5)t²
523 = 2.8t²
186.8 = t²
13.7 s = t
(t = 14 s with proper significant figures)