Answer:
7.8 m/s
Explanation: 
Here object is falling with a gravitational acceleration there  for we can take acceleration = 10 m/ s² and its constant through out the motion there for we can use motion equation 
V = U + at
V - Final velocity 
U - Initial velocity 
a - acceleration 
t - time
V=U+at
107.8=U + 10×10
   = 7.8 m/s
 
        
             
        
        
        
Yes that is correct. We know this because 4.00 x 10 4 Pa is constant. If you have 2.00×10−3m3 then you do the following: (2.00×10^−3)(4.00×10^<span> 4) = </span>8.00×10^−3. That is how you get your answer
        
                    
             
        
        
        
Answer:
i think its D but i could be wrong im sorry if i am
Explanation:
edge 2020
 
        
             
        
        
        
Answer:

Explanation:
The constant speed means that ball is not experimenting acceleration. This elements is modelled by using the following equation of equilibrium:


Now, the exerted force is:

The volume of a sphere is:



Lastly, the force is calculated:


 
        
             
        
        
        
Answer:
The number of bright fringes per unit width on the screen is, 
      
Explanation:
If d is the separation between slits, D is the distance between the slit and the screen and 
 is the wavelength of the light. Let x is the  number of bright fringes per unit width on the screen is given by :

 is the wavelength
n is the order
If n = 1,

So, the the number of bright fringes per unit width on the screen is 
. Hence, the correct option is (B).