Answer:
The magnification is 
Explanation:
From the question we are told that 
   The  power of the lens is  
Generally  
   The object distance is  the negative sign is because the distance is measured in the opposite direction of incident light (i.e away )
 the negative sign is because the distance is measured in the opposite direction of incident light (i.e away )
  Generally the focal length is mathematically represented as 
            
  
    => 
  
   =>  
converting to  cm   
  =>   
Generally from lens equation  we have that  
      
=>  
=>   
Generally the magnification is mathematically represented as 
       
=>    
=>    
 
        
             
        
        
        
Answer:
Power= 0.5hp = 375W
T = 3hrs = 10800s
Power = Work done/ Time
Work = Power * Time = 375 * 10800 = 4050000J
 
        
             
        
        
        
Definition: a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.
        
                    
             
        
        
        
Answer:

Explanation:
It is given that,
Speed of the projectile is 0.5 v. Let h is the height above the ground. Using the first equation of motion to find it.


Initial speed of the projectile is v and final speed is 0.5 v.


g is the acceleration due to gravity
Let h is the height above the ground. Using the second equation of motion as :



So, the height of the projectile above the ground is  . Hence, this is the required solution.
. Hence, this is the required solution.