Question
While working on a physics project at school physics lab, you require a $4 \,\mu F$ capacitor in a circuit across a potential difference of $1 \,kV$. Unfortunately, $4 \,\mu F$ capacitors are out of stock in your lab but $2 \,\mu F$ capacitors which can withstand a potential difference of $400 \,V$ are available in plenty. If you decide to use the $2 \,\mu F$ capacitors in place of $4 \,\mu F$ capacitor, minimum number of capacitors required are

Answer

b
(b)

$C_{A B}=\frac{2}{3}$

Total number of benches $=\frac{{ }^2 \not 4 \times 3}{\not 2}=6$

Total number of capacitors $=6 \times 3=18$

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

Similar questions

A block of metal weighing $2 \,kg$ is resting on a frictionless plane (as shown in figure). It is struck by a jet releasing water at a rate of $1 \,kgs ^{-1}$ and at a speed of $10 \,ms ^{-1}$. Then, the initial acceleration of the block, in $ms ^{-2}$, will be .................
$M$ and $R$ be the mass and radius of a disc. A small disc of radius $R / 3$ is removed from the bigger disc as shown in figure. The moment of inertia of remaining part of bigger disc about an axis $A B$ passing through the centre O and perpendicular to the plane of disc is $\frac{4}{x} M^{2}$. The value of $x$ is __________ .
Image
The circuit has two oppositively connected ideal diodes in parallel. What is the current flowing in the circuit?......$A$
A solid sphere of mass $1\,kg$ rolls without slipping on a plane surface. Its kinetic energy is $7 \times 10^{-3}\,J$. The speed of the centre of mass of the sphere is $.........cm s ^{-1}$.
A closed organ pipe has a fundamental frequency of $1.5\, kHz$. The number of overtones that can be distinctly heard by a person with this organ pipe will be : (Assume that the highest frequency a person can hear is $20,000\, Hz$)
A zener diode of power rating $2\, {W}$ is to be used as a voltage regulator. If the zener diode has a breakdown of $10 \,{V}$ and it has to regulate voltage fluctuated between $6\, {V}$ and $14\, {V}$, the value of ${R}_{{s}}$ for safe operation should be $....\Omega$
A copper rod of $88\; \mathrm{cm}$ and an aluminum rod of unknown length have their increase in length independent of increase in temperature. The length of aluminum rod is....$cm$

$( \alpha_{Cu}=1.7 \times 10^{-5}\; \mathrm{K}^{-1}$ and $\alpha_{Al}=2.2 \times 10^{-5} \;\mathrm{K}^{-1} ) $

If voltage across zener diode is $6\, V$ then find out value of maximum resistance in this condition. (in $k \Omega$)
An electric fan has blades of length $30\, cm$ as measured from the axis of rotation. If  the fan is rotating at $1200 \,r.p.m.$ The acceleration of a point on the tip of the blade is  approximately ........ $m/s^2$.
The plates of parallel plate capacitor are charged upto $100\;V$. A $2\,mm$ thick plate is inserted between the plates. Then to maintain the same potential difference, the distance between the plates is increased by $1.6\;mm$. The dielectric constant of the plate is