Answer:
Sunscreen is like a shield, you would want a better shield to protect you than a weak one so companies try to make their sunscreen better than the rest.
 
        
                    
             
        
        
        
Answer:
Explanation:
Let the internal resistance be r . 
Since in open circuit the volt is 1.55 V , this will be the source voltage .
Source voltage = 1.55 
If external resistance be R .
1.55 / (R + r ) = .500 
R + r = 3.1 ohm 
So sum of internal resistance and external resistance will be 3.1 ohm. 
 
        
             
        
        
        
The mechanical advantage of a machine is the ratio of the force produced by the machine to the force applied to it. Therefore, we may calculate the applied force using:
Mechanical advantage = force by machine / force applied
6 = 2 / force applied
Force applied = 1/3
Thus, the distance that the effort must move will be 1/3 inch
        
                    
             
        
        
        
Explanation:
Nanotechnology is science, engineering, and technology conducted at the nanoscale, which is about 1 to 100 nanometers.
 
        
                    
             
        
        
        
 Answer:
Part(a): The frequency is  .
.
Part(b): The speed of the wave is  .
.
Explanation:
Given:
The distance between the crests of the wave,  .
.
The time required for the wave to laps against the pier, 
The distance between any two crests of a wave is known as the wavelength of the wave. So the wavelength of the wave is  .
.
Also, the time required for the wave for each laps is the time period of oscillation and it is given by  .
.
Part(a):
The relation between the frequency and time period is given by

Substituting the value of  in equation (1), we have
 in equation (1), we have

Part(b):
The relation between the velocity of a wave to its frequency is given by

Substituting the value of  and
 and  in equation (2), we have
 in equation (2), we have
