Electric Charges And Fields MCQs
1. Pick the correct statement
a) The glass rod gives protons to silk when they are rubbed against each other.
b) The glass rod gives electrons to silk when they are rubbed against each other.
c) The glass rod gains protons from silk when they are rubbed against each other.
d) The glass rod gains electrons when they are rubbed against each other.
Answer: (b) The glass rod gives electrons to silk when they are rubbed against each other.
2. A force F acts between two charges +Q and -Q that is placed at a certain distance from each other. The third sphere of charge Q is placed between them. What is the magnitude and force experienced by the third charge?
a) 3F in the direction of +Q charge
b) 4F in the direction of +Q charge
c) 8F in the direction of -Q charge
d) No direction and magnitude is zero
Answer: (c) 8F towards -Q charge
4. At a distance r, two equal charges are kept and they exert a force F on each other. What is the force acting on each charge, if the distance between them is doubled and charges are halved?
a) F/4
b) 4 F
c) F/16
d) F/8
Answer: (c) F/16
5. Pick the correct statement from the following
a) If the point has a charge then the electric field is discontinuous at the point.
b) Continous electric field at a point
c) Continous electric field at a point if a charge is present at the point.
d) At the point, the electric field is discontinuous if a negative charge is present at the point.
Answer: (a) If the point has a charge then the electric field is discontinuous at the point.
6. When is Gauss law true?
a) the speed of light isn’t a universal constant
b) the inverse square law is false
c) magnetic monopoles are present
d) None of the above
Answer: (b) the inverse square law is false
7. What is the SI unit of permittivity of free space?
a) Weber
b) Farad
c) C2N-1m-2
d) C2N-1m2
Answer: (c) C2N-1m-2
8. Pick the true statements about electric field lines
a) It provides information about the direction of the electric field
b) Electric field lines provide information about the type of charge
c) Electric field lines provide information about the field strength
d) All of the above
Answer: (d) All of the above
11. Which surface is considered for Gauss law?
a) Spherical surface
b) Closed Surface
c) Gaussian Surface
d) Plane Surface
Answer: (c) Gaussian Surface
