The formula for frequency is f = 1/T where f is frequency and T is period in seconds. 
You have you period which is 0.008s and that is all you will need to solve or frequency in a wave:
f = 1/2
f = 1/0.008s
f = 125Hz
        
                    
             
        
        
        
Answer:
Subtract the kinetic energy at the bottom from the potential energy loss. The remainder becomes frictional heat.
Potential energy loss: 
M g H = 21.7*9.81*3.5 = 745.1 J
Kinetic energy at bottom of slide: 
= (1/2) M v^2 = 52.5 J
 
        
             
        
        
        
Answer:
The force on one side of  the plate is 3093529.3 N.
Explanation:
Given that,
Side of square plate = 9 m
Angle = 60°
Water weight density = 9800 N/m³
Length of small strip is


The area of strip is

We need to calculate the force on  one side of  the plate
Using formula of pressure


On integrating 




Hence, The force on one side of  the plate is 3093529.3 N.
 
        
             
        
        
        
Newton's second law of motion pertains to the behavior of objects for which all existing forces are not balanced. The second law states that the acceleration of an object is dependent upon two variables - the net force acting upon the object and the mass of the object. The acceleration of an object depends directly upon the net force acting upon the object, and inversely upon the mass of the object. As the force acting upon an object is increased, the acceleration of the object is increased. As the mass of an object is increased, the acceleration of the object is decreased.
        
                    
             
        
        
        
Awww im too late but im going to wait and see if he has it