NEET Physics Electric Charges and Fields MCQs Set A

Question: A point charge + q is placed at a distance d from an isolated conducting plane. The field at a point P on the other side of the plane is
a) directed perpendicular to the plane and away from the plane
b) directed perpendicular to the plane but towards the plane
c) directed radially towards the point charge
d) directed radially away from the point charge
Answer: directed perpendicular to the plane and away from the plane

Question: A hemisphere is uniformely charged positively. The electric field at a point on a diameter away from the centre is directed
a) perpendicular to the diameter
b) parallel to the diameter
c) at an angle tilted towards the diameter
d) at an angle tilted away from the diameter
Answer: perpendicular to the diameter

Question:  Assertion : The positive charge particle is placed in front of a spherical uncharged conductor. The number of lines of forces terminating on the sphere will be more than those emerging from it.
Reason : The surface charge density at a point on the sphere nearest to the point charge will be negative and maximum in magnitude compared to other points on the sphere.
a) If both the Assertion and Reason are incorrect
b) If Assertion is correct but Reason is incorrect
c) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion
d) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
Answer: If both the Assertion and Reason are incorrect

Question:  An electron falls from rest through a vertical distance h in a uniform and vertically upward directed electric field E. The direction of electric field is now reversed, keeping its magnitude the same. A proton is allowed to fall from rest in it through the same vertical distance h. The time of fall of the electron, in comparison to the time of fall of the proton is
a) smaller
b) 5 times greater
c) equal
d) 10 times greater
Answer: smaller

Question:Assertion : On moving a distance two times the initial distance away from an infinitely long straight uniformly charged wire the electric field reduces to one third of the initial value.
Reason : The electric field is inversely proportional to the distance from an infinitely long straight uniformly charged wire.
a) Assertion is correct, reason is correct; reason is a correct explanation for assertion
b) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
c) Assertion is correct, reason is incorrect
d) Assertion is incorrect, reason is correct
Answer:  Assertion is correct, reason is correct; reason is a correct explanation for assertion