NEET Physics Electric Charges and Coulombs Law MCQs Set A

Question: On rubbing, when one body gets positively charged andother negatively charged, the electrons transferred from positively charged body to negatively charged body are
a) valence electrons only
b) electrons of inner shells
c) both valence electrons and electrons of inner shell
d) yet to be established
Answer: valence electrons only

Question: Quantisation of charge implies
a) charge, which is a fraction of a coulomb is not possible.
b) there is a minimum permissible charge on a particle
c) charge exists on particles
d) charge cannot be destroyed
Answer: charge, which is a fraction of a coulomb is not possible.

Question: What happens when some charge is placed on a soap bubble?
a) Its radius increases
b) None of these
c) Its radius decreases
d) The bubble collapses
Answer: Its radius increases

Question:  Which of the following statements is incorrect?
I. The charge q on a body is always given by q = ne, where n is any integer, positive or negative.
II. By convention, the charge on an electron is taken to be negative.
III. The fact that electric charge is always an integral multiple of e is termed as quantisation of charge.
IV. The quatisation of charge was experimentally demonstrated by Newton in 1912.
a) Only IV
b) Only I
c) Only II
d) Only III
Answer: Only IV

Question:

a) 1 : 3
b) 1 : 2
c) 2 : 1
d) 3 : 1
Answer: 1 : 3

Question: 1 C charge is equivalent to charge on how much number of protons?
a) 6 × 10¹⁸
b) 8 × 10²⁰
c) 7 × 10¹⁹
d) 9 × 10²¹
Answer: 6 × 10¹⁸

Question: When a body is charged by induction, then the body
a) does not lose any charge
b) becomes neutral
c) loses whole of the charge on it
d) loses part of the charge on it
Answer:  does not lose any charge

Question: On charging by conduction, mass of a body may
a) increase or decrease
b) increase
c) decreases
d) None of these
Answer: increase or decrease

Question:  Select the correct statements, Coulomb's law correctly describes the electric force that
I. binds the electrons of an atom to its nucleus.
II. binds the protons and neutrons in the nucleus of anM atom.
III. binds atoms together to form molecules.
a) II and III
b) I and II
c) I and III
d) I, II and III
Answer:  II and III

Question:

a) Principle of superposition
b) Coulomb’s law
c) Newton’s
d) Net electric flux out the position of +q.
Answer: Principle of superposition

More Questions.....................................

Question:  Which of the following graphs shows the correct variation of force when the distance r between two charges varies ?
a)

b)

c)

d)

Answer:

Question:
Assertion : The property that the force with which two charges attract or repel each other are not affected by the presence of a third charge.
Reason : Force on any charge due to a number of other charge is the vector sum of all the forces on that charge due to other charges, taken one at a time.
a) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
b) Assertion is correct, reason is incorrect
c) Assertion is incorrect, reason is correct
d) Assertion is correct, reason is correct; reason is a correct explanation for assertion
Answer: Assertion is correct, reason is correct; reason is not a correct explanation for assertion

Question: The metal knob of a gold leaf electroscope is touched witha positively charged rod. When it is taken away the leaves stay separated. Now the metal knob is touched by negatively charged rod. The separation between the leaves
a) decreases
b) increases
c) remains same
d) first increases then decreases.
Answer: decreases

Question:  Two identical metal spheres A and B are supported on insulating stands and placed in contact. What kind of charges will A and B develop when a negatively charged ebonite rod is brought near A?
a) A will have a positive charge and B will have a negative charge
b) A will have a negative charge and B will have a positive charge
c) Both A and B will have positive charges
d) Both A and B will have negative charges
Answer: A will have a positive charge and B will have a negative charge

Question: The force of repulsion between two electrons at a certain distance is F. The force between two protons separated by the same distance is (m_p=1836_me)
a) F
b) 3 F
c) 2 F
d) 1836 F
Answer:  F

Question:  The force between two small charged spheres having charges of 1 × 10^–7 C and 2 × 10^–7 C placed 20 cm apart in air is
a) 4.5 × 10^–3 N
b) 5.4 × 10^–3 N
c) 4.5 × 10^–2 N
d) 5.4 × 10^–2 N
Answer:  4.5 × 10^–3 N

Question:

a)

b)

c)

d)

Answer:

Question: Two insulated charged metalic sphere P and Q have their centres separated by a distance of 60 cm. The radii of P and Q are negligible compared to the distance of separation. The mutual force of electrostatic repulsion if the charge on each is 3.2 × 10^–7 C is 
a) 2.5 × 10^–3 N
b) 3.5 × 10^–4 N
c) 5.2 × 10^–4 N
d) 1.5 × 10^–3N
Answer:  2.5 × 10^–3 N

Question:

a) 16 × 10^–3 N
b) 9 × 10^–2 N
c) 9 × 10³ N
d) 10^–3 N
Answer:  16 × 10^–3 N

Question: If a charge q is placed at the centre of the line joining two equal charges Q such that the system is in equilibrium then the value of q is
a) –Q/4
b) Q/4
c) –Q/2
d) Q/2
Answer:  –Q/4

Question:

a)

b)

c)

d)

Answer:

Question:  The electric charge required to expand a soap bubble to twice its dimension is

a)

b)

c)

d) None of these

Answer:

Question: A large nonconducting sheet M is given a uniform chargedensity. Two uncharged small metal rods A and B are placed nea r the sheet as shown in figure. Then

a) All of these
b) A attracts B
c) M attracts B
d) M attracts A
Answer:  All of these

Question:

a) Assertion is correct, reason is correct; reason is not a correct explanation for assertion
b) Assertion is correct, reason is correct; reason is 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 not a correct explanation for assertion

Question:

a)

b)

c)

d)

Answer:

Question:

a)

b)

c)

d)

Answer:

Question:

a)

b)

c)

d)

Answer:

Question:  A solid conducting sphere of radius a has a net positive charge 2Q. A conducting spherical shell of inner radius b and outer radius c is concentric with the solid sphere and has a net charge – Q.The surface charge density on the inner and outer surfaces of the spherical shell will be

a)

b)

c)

d) None of the above

Answer:

Question:  Two pith balls carrying equal charges are suspended from a common point by strings of equal length. The equilibrium separation between them is r. Now the strings are rigidly clamped at half the height. The equilibrium separation between the balls now become

a)

b)

c)

d) None of these
Answer:

Question:

a) 16 × 10^–3 N
b) 9 × 10^–2 N
c) 9 × 10³ N
d) 10^–3 N
Answer: 16 × 10^–3 N

Question:  A total charge Q is broken in two parts Q₁ and Q₂ and they are placed at a distance R from each other. The maximum force of repulsion between them will occur. when

a)

b)

c)

d)

Answer:

Question:   Two particles A and B having equal charges are placed at a distance d apart. A third charged particle placed on the perpendicular bisection of AB at distance x. The third particle experiences maximum force when

a)

b)

c)

d)

Answer:

Question:

a)

b)

c)

d) None of these

Answer:

Question:

a) > mg
b) < mg
c) mg
d) None of these
Answer:  > mg

Question:

a)

b)

c)

d)

Answer:

Question:  Force between two identical charges placed at a distance of r in vacuum is F. Now a slab of dielectric of dielectric contrant 4 is inserted between these two charges. If the thickness of the slab is r/2, then the force between the charges will become

a)

b)

c)

d)

Answer:

Question:

a)

b)

c)

d) 1

Answer:

Question:

a) 3.7 × 10^–3 C
b) 3.7 × 10^–6 C
c) 7.3 × 10^–3C
d) 7.3 × 10^–6 C
Answer: 3.7 × 10^–3 C

Question: Two insulated charged metalic sphere P and Q have their centres separated by a distance of 60 cm. The radii of P and Q are negligible compared to the distance of separation. The mutual force of electrostatic repulsion if the charge on each is 3.2 × 10^–7 C is 
a) None of these
b) 3.5 × 10^–4 N
c) 5.2 × 10^–4 N
d) 1.5 × 10^–3 N
Answer:  None of these