Answer:  Sound waves are a waves of compression and rarefaction, by which sound is propagated in an elastic medium such as air.
Explanation:
In physics, sound is a vibration that propagates as an acoustic wave, through a transmission medium such as a gas, liquid or solid.
 
        
                    
             
        
        
        
Answer:
50 kg
Explanation:
 fnet=ma
600-200=m8
divide both side by 8 to make m the subject of the formula Thus m=50kg
 
        
             
        
        
        
Answer: 4.7m/s²
Explanation:
According to newton's first law,
Force = mass × acceleration
Since we are given more the one force, we will take the resultant of the two vectors.
Mass = 2.0kg
F1+F2 = (3i-8j)+(5i+3j)
Adding component wise, we have;
F1+F2 = 3i+5i-8j+3j
F1+F2 = 8i-5j
Resultant of the sum of the forces will be;
R² = (8i)²+(-5j)²
Since i.i = j.j = 1
R² = 8²+5²
R² = 64+25
R² = 89
R = √89
R = 9.4N
Our resultant force = 9.4N
Substituting in the formula
F = ma
9.4 = 2a
a = 9.4/2
a = 4.7m/s²
Therefore, magnitude of the acceleration of the particle is 4.7m/s²
 
        
             
        
        
        
Answer:
b is the answer tennis ball
 
        
             
        
        
        
Hey there!
the answer is 
C. a tennis racket striking a tennis ball
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