Short notes
Objective questions (Answers are given below)
The unit of absolute permittivity of a medium is
(a) joule/coulomb
(b) newton-metre
(c) farad/metere
(d) farad/coulomb
- If relative permittivity of mica is 5, its absolute permittivity is
(a) 5 ε0 (b) 5/ε0
(b) 5/ε0 (c) ε0/5 (d) 8.854 × 10−12 - Two similar electric charges of 1 C each are placed 1 m apart in air. Force of repulsion between them would be nearly…… newton
(a) 1
(b) 9 × 109
(c) 4 π
(d) 8.854 × 10−12
- Electric flux emanating from an electric
charge of + Q coulomb is
(a) Q/ε0 (b) Q/εr
(c) Q/ε0εr (d) Q - The unit of electric intensity is
(a) joule/coulomb
(b) newton/coulomb (c) volt/metre (d) both (b) and (c)
- If D is the electric flux density, then value
of electric intensity in air is
(a) D/ε0 (b) D/ε0εr
(c) dV/dt (d) Q/εA - For any medium, electric flux density D is
related to electric intensity E by the equation
(a) D = ε0 E (b) D = ε0εr E
(c) D = E/ε0εr (d) D = ε0E/εr - Inside a conducting sphere,…remains
constant
(a) electric flux
(b) electric intensity
(c) charge
(d) potential - The SI unit of electric intensity is
(a) N/m
(b) V/m
(c) N/C
(d) either (b) or (c)
- According to Gauss’s theorem, the surface
integral of the normal component of electric
flux density D over a closed surface containing
charge Q is
(a) Q (b) Q/ε0
(c) ε0 Q (d) Q2/ε0 - Which of the following is zero inside a
charged conducting sphere ?
(a) potential
(b) electric intensity
(c) both (a) and (b)
(d) both (b) and (c) - In practice, earth is chosen as a place of zero
electric potential because it
(a) is non-conducting
(b) is easily available
(c) keeps lossing and gaining electric
charge every day
(d) has almost constant potential.
- c 2. a 3. b 4. d 5. d 6. a 7.b 8. d 9. d 10. a 11. c 12. d