The kinetic energy of an object is directly proportional to its mass and the square of its velocity
KE = 1/2 (mv²)
KE = Kinetic Energy
m = mass in kg
v = velocity in m/s
Given:
m = .8 kg
v =  11.2 m/s
Substitute:
KE = 1/2 (.8)(11.2²)
KE = 50.18 J
        
                    
             
        
        
        
<span>The forces of nature are phase forces.</span>
        
             
        
        
        
Answer:
a) Time = 2.67 s
b) Height = 35.0 m
Explanation:
a) The time of flight can be found using the following equation:
 (1)
   (1)
Where:
 : is the final position in the horizontal direction = 80 m
: is the final position in the horizontal direction = 80 m
 : is the initial position in the horizontal direction = 0
: is the initial position in the horizontal direction = 0
 : is the initial velocity in the horizontal direction = 30 m/s
: is the initial velocity in the horizontal direction = 30 m/s
a: is the acceleration in the horizontal direction = 0 (the stone is only accelerated by gravity)
t: is the time =?   
By entering the above values into equation (1) and solving for "t", we can find the time of flight of the stone:    

b) The height of the hill is given by:
 
 
Where:
 : is the final position in the vertical direction = 0
: is the final position in the vertical direction = 0
 : is the initial position in the vertical direction =?
: is the initial position in the vertical direction =?
 : is the initial velocity in the vertical direction =0 (the stone is thrown horizontally)
: is the initial velocity in the vertical direction =0 (the stone is thrown horizontally)            
g: is the acceleration due to gravity = 9.81 m/s²
Hence, the height of the hill is:
 
  
I hope it helps you! 
 
        
             
        
        
        
I believe the answer would be C because potential energy is affected by height and mass. The truck in photo C is the highest and has a lot of mass.
        
             
        
        
        
Answer:
This can be used to find out the speed of the returned journey. The equation means speed = returned distance ÷ time.
Explanation: