Answer:
F = f from Newton’s first law.
Explanation:
since the desk is moved in a straight line at a constant speed, newton first law tell us that the two forces must be equal.
Newton's First Law states that an object will remain at rest or in uniform motion in a straight line unless acted upon by an external force. since the table has been set in motion by the 400 N force, it will remain in motion unless it is been acted upon by an external force, and this means that the 400 N must be equal to the frictional force for it to have been in motion in the first instance.
Initial velocity: 0
final velocity: 7 m/s
a = 3.6
t = ?
x = ?
(7-0)/3.6 = t
t = 1.94 s
The visible spectrum of the electromagnetic spectrum is made up of "<span>red, orange, yellow, green, blue, and violet light"
In short, Your Answer would be Option C
Hope this helps!</span>
200N is the answer (at least thats what I think)