Answer:
efficiancy=40 percent
Explanation:
efficiency=energy output/energy input×100
efficiancy=8J/20J×100
efficiancy=0.4×100
efficiancy=40 percent
Mark brianliest if my answer suit your question..
 
        
                    
             
        
        
        
A transverse wave is a moving wave in which the current is perpendicular to the direction of the wave or path of propagation. A longitudinal wave are waves in which the displacement of the median is in the direction of the propagation. 
Example:
Transverse- pond ripple
Longitudinal- crest and troff
        
                    
             
        
        
        
It stops accelerating when the air resistance is equal to its weight.
That's (m•g) 
= (2 kg) • (9.8 m/s^2)
= 19.6 newtons
        
             
        
        
        
Hi there!
Great question!
Basketballs have air inside them. A special pump is used to insert the air. That's why you can lift the basketballs off the ground easily. If it was a solid, though, you'd hardly be able to lift the ball up! Basketballs can float, too, because anything with air inside can float. If it were solid, it would sink in the water easily.
Hope this helps! :D
        
             
        
        
        
The vertical components of velocity is  10.35 m/s and the horizontal component of velocity is 38.6 m/s
<h3>What are the components of velocity?</h3>
We know that velocity is a vector quantity, a vector often can be resolved into its components. The vertical components is V sinθ while the horizontal component is vcosθ.
Hence;
Vertical component = 40 m/s sin 15 degrees = 10.35 m/s
Horizontal component = 40 cos 15 degrees = 38.6 m/s
Learn more about components of velocity:brainly.com/question/14478315
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