Shadows are formed when an opaque object or an object that doesn't allow light to pass through is in the way or infront of etc. a source of light.
        
                    
             
        
        
        
Using the "v = f. λ" <span>equation...
 
Your "v" or </span>velocity = 156.25 meters/second
        
             
        
        
        
Answer:
  L  = 1.15 m
Explanation:
The diffraction phenomenon is described by the equation
         a sin θ = m λ
Where a is the width of the slit, λ  the wavelength and m is an integer, the order of diffraction is left.
The diffraction measurements are made on a screen that is far from the slit, and the angles in the experiment are very small, let's use trigonometry
           tan θ = y / L
           tan θ = sint θ / cos θ≈ sin θ
We substitute in the first equation
            a (y / L) = m λ
 The first maximum occurs for m = 1
The distance is measured from the center point of maximum, which coincides with the center of the slit, in this case the distance is the total width of the central maximum, so the distance (y) measured from the center is
          y = 1.15 / 2 = 0.575 cm
          y = 0.575 10⁻² m
 Let's clear the distance to the screen (L)
        L = a y / λ  
Let's calculate
      L = 115 10⁻⁶  0.575 10⁻² / 575 10⁻⁹
      L  = 1.15 m
 
        
             
        
        
        
Answer:
A simple pulley is a wheel with a rope that allows you to pull one end and have it lift whatever is on the other end. A modern, common example of this is a crane, often used in construction.
Explanation: