Answer: Gravitational force
Explanation:
A non contact force can be described as a force applied to an object by another body that is not in direct contact with it. 
For example, an object thrown upwards will return back due to the force of gravity acting on it. So, it means Gravitational force is acting on the body without necessarily being in contact with that body. 
 
        
             
        
        
        
<span>node spacing = half of wavelength = 3 cm
velocity = 10 cm/s = freq * wavelength
hench freq = 10/6 = 5/3 = 1.7 hz</span>
        
                    
             
        
        
        
The answer is "D". This is because wind is very abundant on earth...
 
        
                    
             
        
        
        
Answer:
The frequency is the same
Explanation:
When a wave is created by a source which is vibrating at a certain frequency, the frequency of the wave itself is equal to the frequency of the source.
This occurs with every kind of wave. For instance, if we consider the radio waves produced by an antenna, the frequency of the radio waves is equal to the frequency of the antenna.
In this case, the waves are created by the vibrating bug. The bug is vibrating with a certain frequency  : as a consequence, the frequency
: as a consequence, the frequency  of the waves produced by the bug will be equal to the frequency of vibration of the bug:
 of the waves produced by the bug will be equal to the frequency of vibration of the bug:
 .
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