Answer:

Explanation:
When a standing wave is formed with six loops means the normal mode of the wave is n=6, the frequency of the normal mode is given by the expression:

Where  is the length of the string and
 is the length of the string and  the velocity of propagation. Use this expression to find the value of
 the velocity of propagation. Use this expression to find the value of  .
.

The velocity of propagation is given by the expression:

Where  is the desirable variable of the problem, the linear mass density, and
 is the desirable variable of the problem, the linear mass density, and  is the tension of the cord. The tension is equal to the weight of the mass hanging from the cord:
 is the tension of the cord. The tension is equal to the weight of the mass hanging from the cord:

With the value of the tension and the velocity you can find the mass density:


 
        
             
        
        
        
Answer:
 t₁ = 3 s
Explanation:
In this exercise, the vertical displacement equation is not given
         y = 240 t + 16 t²
Where y is the displacement, 240 is the initial velocity and 16 is half the value of the acceleration
Let's replace
       864 = 240 t + 16 t²
Let's solve the second degree equation
     16 t² + 240 t - 864 = 0
Let's divide by 16
     t² + 15 t - 54 = 0
The solution of this equation is
      t = [-15 ± √(15 2 - 4 1 (-54)) ] / 2 1
      t = [-15 ±√(225 +216)] / 2
      t = [-15 + - 21] / 2
We have two solutions.
      t₁ = [-15 +21] / 2
      t₁ = 3 s
      t₂ = -18 s
Since time cannot have negative values, the correct t₁ = 3s
 
        
             
        
        
        
Answer:In the case of burning wood, stored potential energy (in the form of chemical energy) in the log is released due to heating by other excited atoms. This chemical reaction is called combustion and requires oxygen. Combustion changes the potential chemical energy into kinetic energy in the form of heat.
Explanation:
 
        
                    
             
        
        
        
Answer:
Only circuit A will contain to lit bulbs
 
        
             
        
        
        
Answer is a) the force caused by the wend nag encountering wind and air.