Here, height is given which will be the distance for a freely falling object.
The velocity will be

and the acceleration will be

In this way, the formula works.
 
        
             
        
        
        
Explanation:
Average acceleration is change in velocity over time.
a = Δv / Δt
a = (22.0 m/s − (-25.0 m/s)) / 0.00350 s
a = 13,400 m/s²
 
        
             
        
        
        
The electric field is always perpendicular to the surface outside of a conductor. TRUE
<span> If an electron were placed on an electric field line, it would move in a direction perpendicular to the field. FALSE, it would move in an anti-parallel direction because its charge is negative </span>
 
<span>Electric field lines originate on positive charge and terminate on negative charge. TRUE ; but they can also go to infinity </span>
 
It is possible for two electric field lines to cross each other.
<span> Usually FALSE; though technically possible at special points where field is zero. </span>
 
If an electron and a positron were in the presence of a very strong electric field, they would move away from each other.
<span> TRUE; one is positive, and one is negative. If the field is strong enough, the action of the field will overcome the mutual attraction between them </span>
 
It is not possible for the electric field to ever be zero. FALSE: it IS possible, inside a conductor for instance
   
If a proton were placed on an electric field line, it would move in a direction anti-parallel to the field.
<span> FALSE: being positive, it would move in the SAME direction as the field</span>ic