Q.1. What about Gauss’s theorem is not incorrect?
(a) It can be derived by using Coulomb’s Law
(b) It is valid for conservative field obeys inverse square root law
(c) Gauss’s theorem is not applicable in gravitation
(d) Both (a) & (b)
Answer
Answer: (d)Q.2. A uniformly charged conducting sphere of 4.4 m diameter has a surface charge density of 60 μC m–2. The charge on the sphere is
(a) 7.3 × 10–3 C
(b) 3.7 × 10–6 C
(c) 7.3 × 10–6 C
(d) 3.7 × 10–3 C
Answer
Answer: (d)Q.3. Gauss’s law is true only if force due to a charge varies as
(a) r–1
(b) r–2
(c) r–3
(d) r–4
Answer
Answer: (b)Q.4. A hollow sphere of charge does not have electric field at
(a) outer point
(b) interior point
(c) beyond 2 m
(d) beyond 100 m
Answer
Answer: (b)Q.5. The Gaussian surface
(a) can pass through a continuous charge distribution.
(b) cannot pass through a continuous charge distribution.
(c) can pass through any system of discrete charges.
(d) can pass through a continuous charge distribution as well as any system of discrete charges.
Answer
Answer: (a) Gaussian surface cannot pass through any discrete charge because electric field due to a system of discrete charges is not well defined at the location of the charges. But the Gaussian surface can pass through a continuous charge distribution.Q.6. Charge motion within the Gaussian surface gives changing physical quantity
(a) electric field
(b) electric flux
(c) charge
(d) gaussian surface area
Answer
Answer: (a)Q.7. Select the correct statements from the following.
I. The electric field due to a charge outside the Gaussian surface contributes zero net flux through the surface.
II. Total flux linked with a closed body, not enclosing any charge will be zero.
III. Total electric flux, if a dipole is enclosed by a surface is zero.
(a) I and II
(b) II and III
(c) I and III
(d) I, II and III
Answer
Answer: (d)Q.8. Gauss’s law is valid for
(a) any closed surface
(b) only regular close surfaces
(c) any open surface
(d) only irregular open surfaces
Answer
Answer: (a) Gauss’s law is valid for any closed surface, no matter what its shape or size.Q.9. The electric field due to an infinitely long straight uniformly charged wire at a distance r is directly proportional to
(a) r
(b) r2
(c) 1/r
(d) 1/r2
Answer
Answer: (c)Q.10. Figure shows the part of an infinite plane sheet of charge.
Which of the following graphs correctly shows the behaviour of electric field intensity as we move from point O to A.
