Answer:
The friction force is 250 N
Explanation:
The desk is moving at constant velocity. This means that its acceleration is zero: a = 0. Newton's second law states that the resultant of the forces acting on the desk is equal to the product between mass (m) and acceleration (a):

In this case, we know that the acceleration is zero: a = 0, so also the resultant of the forces must be zero:
 (1)
 (1)
We are only interested in the forces acting along the horizontal direction, since it is the direction of motion. There are two forces acting in this direction:
- the pull, forward, F = 250 N
- the friction force, backward, 
Given (1), we have

So the force of friction must be equal to the pull:

 
        
             
        
        
        
Answer:
electric
<em>please give brainliest</em>
 
        
             
        
        
        
A light meter, because illu is a root for light
        
                    
             
        
        
        
Answer:
potential energy at origin is 
Explanation:
given data:
electric field E = 5*10^{6} N/C
at x = 43 cm, y = 28 cm
distance btween E and origin


potential energy per unit charge 


potential energy at origin is 2.57*10^{6} volt
 
        
             
        
        
        
Answer:
The acceleration of Abbie is half of the Zak's. 
Explanation:
The centripetal acceleration of an object on a circular path is given by :

Two children are riding on a merry-go-round that is rotating with a constant angular speed. Let  is distance of Abbie from the merry-go-round and
 is distance of Abbie from the merry-go-round and  is distance of Zak's from the merry-go-round. Acceleration of Abbie is :
 is distance of Zak's from the merry-go-round. Acceleration of Abbie is :
 ...... (1)
 ...... (1)

Acceleration of Zak's is :
 .......(2)
 .......(2)

Dividing equation (1) and (2) we get :

So, the acceleration of Abbie is half of the Zak's.