# 12th HSC Physics - One Mark Important Questions

Our next batch of practice questions for 12th HSC Physics Examinations. Practice these sample questions well and post your working answers in the comments section if you know it..If you have any important questions for sharing, post it for us.

1) The electric field due to a point charge of $8 \;\mu C$ at a distance 20 cm from the point is:

a) $36\times10^{7}\;NC^{-1}$

b) $18\times10^{-1}\;NC^{-1}$

c) $18\times10^{9}\;NC^{-1}$

d) $36\times10^{9}\;NC^{-1}$

2) Electric field intensity is 400 $400\;Vm^{-1}$ at a distance of 2 m from a point charge. It will be $100\;Vm^{-1}$ at a distance?

a) 50 cm

b) 4 cm

c) 4 m

d) 1.5 m

3) A $400\;pF$ is charged by 1000 V battery. The electrostatic energy stored by the capacitor is:

a) $2\times10^{-4}\;J$

b) 0.02 J

c) 0.002 J

d) $2\times10^{-6}\;J$

4) The unit of electric field intensity is:

a) $Vm^{-1}$

b) $CN^{-1}$

c) $VC^{-1}$

d) $NC^{-1}$

5) Electric potential energy of two point charges is given by:

a) $\mu =\frac{q_{1}q_{2}}{4\pi\varepsilon_{0}r^2}$

b) u = –PE cos 0

c) $\mu =\frac{q_{1}q_{2}}{4\pi\varepsilon_{0}r}$

d) u = –PE sin 0

6) Which of the following is not a conductor?

a) Mercury

c) Air

d) Platinum

7) The magnitude of electric charge (e) is:

a) $1.6\; \times 10^{-19} \;C$

b) $6.024\; \times 10^{-24} \;C$

c) $3.2\; \times 10^{-19} \;C$

d) $6.624\; \times 10^{-34} \;C$

8) The capacitance of a capacitor is given by:

a) C = qV

b) C = q/V

c) C = qA

d) C = $\sigma$A

9) Van de Graaff generator produces large electro static potential difference of the order of:

a) $10^{3} \;V$

b) $10^{5} \;V$

c) $10^{7} \;V$

d) $10^{9} \;V$

10) Total charge in $_{92}U^{238}$ is:

a) +92 e

b) +238 e

c) +330 e

d) +146 e

11) An electric dipole of charges $2 \times \; 10^{-6} \;C$, $-2 \times \; 10^{-6} \;C$ are separated by a distance 1 cm. The electric field due o dipole at a point on its axial line 1 m from its centre will be:

a) 36 N/C

b) 18 N/C

c) 180 N/C

d) 360 N/C

12) The area of each plate of a parallel plate capacitor is $4 \times \; 10^{-2} sq m$. If the thickness of the dielectric medium between the plates $10^{-3} \;m$ and the relative permitivity of the dielectric is 7. The capacitance of the capacitor will be?

a) $2.479 \times \; 10^{-9} \;F$

b) $1.479 \times \; 10^{-9} \;F$

c) $2.479 \times \; 10^{-6} \;F$

d) $1.479 \times \; 10^{-6} \;F$

13) A capacitance of $2 \;\muF$ is given a charge of 10 C. If the charge on the capacitor is tripled, then the capacitance is:

a) $6 \;\muF$

b) $6.67 \;\muF$

c) $150 \;\muF$

d) $5 \;\muF$

14) Total flux over a closed surface of charge q is:

a) $4\pi q$

b) $36\pi \; \times 10^{9} \;q$

c) $9 \; \times 10^{9} \;q$

d) $4\pi \; \times 10^{9} \;q$

15) The resultant electric field at any point between two parallel charged sheets is:

a)$E=\frac{\sigma}{2\varepsilon_{0}}$

b) $E=\frac{-\sigma}{2\varepsilon_{0}}$

c) $E=\frac{\sigma}{\varepsilon_{0}}$

d) $E=\frac{2\sigma}{\varepsilon_{0}}$