Answer:
The magnitude of electric field is 22.58 N/C
Solution:
Given:
Force exerted in upward direction, 
Charge, Q = 
Now, we know by Coulomb's law,

Also,
Electric field, 
Thus from these two relations, we can deduce:
F = QE
Therefore, in the question:



Here, the negative side is indicative of the Electric field acting in the opposite direction, i.e., downward direction.
The magnitude of the electric field is:

0.120L + 2.345L = 2.465L = 4 significant figures in the answer
The answer is (a) because movement is acceleration
Answer:
First one, third one, and fourth one
Answer:
C) W = - 190 J
Explanation:
Notation
Wf = work done by the friction force (unknown)
Ff = force of the friction
d = distance travelled by the box = (2 pi 1.82 m) = 11.435 m