There exists a uniform electric field E=4 10^5 ,Vm ^ -1 directed … - Vidyadip

MCQ

There exists a uniform electric field $E=4 \times 10^5 \,Vm ^{-1}$ directed along negative $x$-axis such that electric potential at origin is zero. Acharge of $-200 \,\mu C$ is placed at origin, and a charge of $+200 \,\mu C$ is placed at $(3 \,m , 0)$. The electrostatic potential energy of the system is ...........$J$

✓
$120$
B
$-120$
C
$-240$
D
$0$

✓

Answer

Correct option: A.

$120$

a
(a)

$V_3=4 \times 10^5 \times 3=12 \times 10^5$

$U=\frac{k q_1 q_2}{r}+q_1 V_2+q_2 V_2$

$U=\frac{-9 \times 10^9 \times 200 \times 200 \times 10^{-12}}{3}+(-200)(0)+200\left(12 \times 10^5\right) \times 10^{-6}$

$U=-120+240$

$U=120 \,J$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q (1 Marks)" from 2. Electric potential and capacitance→2. Electric potential and capacitance — all question types→Physics STD 12 Science question papers→CBSE Board STD 12 Science question papers→CBSE Board question paper generator→

Similar questions

A proton, a neutron, an electron and an $\alpha\,-$particle have same energy. If $\lambda_{ p }, \lambda_{ n }, \lambda_{ e }$ and $\lambda_{\alpha}$ are the de Broglie's wavelengths of proton, neutron, electron and $\alpha$ particle respectively, then choose the correct relation from the following

Which of the following is not a basic property of magnets.

There is a current of 40 ampere in a wire of $10^{-6}m^2$ area of cross-section. If the number of free electron per $m^3$ is $10^{29}$, then the drift velocity will be

Three capacitors each of capacity $ 4μ\text{F}$ are to be connected in such a way that the effective capacitance is $6μ\text{F}$. This can be done by:

A power transformer (step up) with an $1 : 8$ turn ratio has $60\, Hz, 120\, V$ across the primary; the load in the secondary is $10^4\ \Omega$. The current in the secondary is :-

A thin glass (refractive index $1.5$) lens has optical power of $ - \,5D$ in air. It's optical power in a liquid medium with refractive index $1.6$ will be

In the given potentiometer circuit length of the wire $AB$ is $3\,m$ and resistance is $R = 4.5 \,\Omega.$ The length $AC$ for no deflection in galvanometer is ................ $\mathrm{m}$

$10\,Cells$, each of emf $'E'$ and internal resistance $'r'$, are connected in series to a variable external resistance. Figure shows the variation of terminal potential difference of their combination with the current drawn from the combination.$Emf$ of each cell is ............. $V$

A ball is projected from top of the table with initial speed $u$ at an angle of inclination $q$, motion of image of ball w.r.t ball

In an FM system a 7 kHz signal modulates 108 MHz carrier so that frequency deviation is 50 kHz. The carrier swing is