Answer:
When an atom has an equal number of electrons and protons, it has an equal number of negative electric charges (the electrons) and positive electric charges (the protons). The total electric charge of the atom is therefore zero and the atom is said to be neutral.
Explanation:
 
        
                    
             
        
        
        
When sounds at two different frequencies are combined,
two new sounds are created ... at the sum and difference
of the original frequencies.
Combining two sounds at 490 Hz and 488 Hz creates
beats at  978 Hz and 2 Hz.
The fluttering "wah wah" effect of the 2 Hz beat is much more 
noticeable than the new sound at 978 Hz.
        
             
        
        
        
The property that compares the mass of an object with its volume is density.
        
                    
             
        
        
        
Answer:
E= -3.166 cosωt   V
Explanation:
Given that
I = Imax sinωt
L= 8.4 m H
Imax= 4 A
 f = ω/2π = 60.0 Hz
ω = 120π  rad/s
We know that self induce E given as




E= -3166.72 cosωt  m V
E= -3.166 cosωt   V
This is the induce emf.