Answer:
because some waste heat is always produced produced in a heat engine.
Explanation:
the fraction of heat input that is converted to a net work output is a measure of the performance of the heat engine and is called the thermal efficiency.Since the machine does not contain a source of energy ,nor can it store energy ,from this conversation of energy the power output of machine can never be greater than its input,so efficiency can be less than 100%.
 
        
                    
             
        
        
        
Answer:The energy of the wave by a factor of 4
Explanation:
 
        
             
        
        
        
The time spent in the air by the ball at the given momentum is 6.43 s.
The given parameters;
- <em>momentum of the ball, P = 0.9 kgm/s</em>
- <em>weight of the ball, W = 0.14 N</em>
The impulse experienced by the ball is calculated as follows;

where;
 is impulse
 is impulse
 is change in momentum
 is change in momentum
The time of motion of the ball is calculated as follows;

Thus, the time spent in the air by the ball at the given momentum is 6.43 s.
Learn more here:brainly.com/question/13468390
 
        
             
        
        
        
Explanation:
Below is an attachment containing the solution. 
 
        
             
        
        
        
Answer:
24erfvtgvcd2s
Explanation:
2d343f5vrc3344drews3wqqeq