Answer:
8 seconds
Explanation:
From Newton's second law;
Ft = m(v-u)
F = Force applied
t = time taken
v = final velocity
u  = initial velocity
20 * t = 32 (9 - 4)
20t = 32 * 5
t = 32 * 5/ 20
t = 8 seconds
 
        
             
        
        
        
Answer: True
Explanation:
Mass is the amount of matter in an object. Everything is made up of matter. 
 
        
                    
             
        
        
        
Well, first of all, I don't think "After the collapse of a nebular cloud ..." 
is the first time that "atoms begin gravitating together".  Seems to me like 
that's what was going on all the time, and it's what caused the nebular cloud 
to collapse in the first place.
In any case, once the pressure and temperature at the center get high enough, 
you get "ignition" of nuclear fusion, and that's when you first have a "star".  
        
                    
             
        
        
        
Answer:

Explanation:
Here we know that the EMF induced in this Field is given as

here B = perpendicular component of magnetic field
v = speed of the bird
L = length of the wings
now we have



now we have


 
        
             
        
        
        
Answer:

Explanation:
The mass of one electron is

So the number of electrons contained in M=1.7 kg of mass is

The charge of one electron is

So, the total charge of these electrons is equal to the charge of one electron times the number of electrons:
