A mixture of light, consisting of wavelength

Question: A mixture of light, consisting of wavelength $590 \mathrm{~nm}$ and an unknown wavelength, illuminates Young's double slit and gives rise to two overlapping interference patterns on the screen. The central maximum of both lights coincide. Further, it is observed that the third bright fringe of known light coincides with the 4 th bright fringe of the unknown light. From this data, the wavelength of the unknown light is :- $442.5 \mathrm{~nm}$$776.8 \mathrm{~nm}$$393.4 \mathrm{~nm}$$885....

Solve this following

Question: A pipe of length $85 \mathrm{~cm}$ is closed from one end. Find the number of possible natural oscillations of air column in the pipe whose frequencies lie below $1250 \mathrm{~Hz}$. The velocity of sound in air is $340 \mathrm{~m} / \mathrm{s}$. 64128Correct Option: 1 Solution:...

In an experiment the angles are required to be measured

Question: In an experiment the angles are required to be measured using an instrument 29 divisions of the main scale exactly coincide with the 30 divisions of the vernier scale. If the smallest division of the main scale is half-a-degree $\left(=0.5^{\circ}\right)$, then the least count of the instrument is :-One degreeHalf degreeOne minuteHalf minuteCorrect Option: , 3 Solution:...

A motor cycle starts from rest and accelerates along a straight path

Question: A motor cycle starts from rest and accelerates along a straight path at $2 \mathrm{~m} / \mathrm{s}^{2}$. At the starting point of the motor cycle there is a stationary electric siren. How far has the motor cycle gone when the driver hears the frequency of the siren at $94 \%$ of its value when the motor cycle was at rest ? $\left(\right.$ Speed of sound $=330 \mathrm{~ms}^{-1}$ ) :- $147 \mathrm{~m}$$196 \mathrm{~m}$$49 \mathrm{~m}$$98 \mathrm{~m}$Correct Option: , 4 Solution:...

The reading of the ammeter for a silicon diode in the given circuit is

Question: The reading of the ammeter for a silicon diode in the given circuit is :- $15 \mathrm{~mA}$$11.5 \mathrm{~mA}$$13.5 \mathrm{~mA}$0Correct Option: Solution:...

Statement-1 : Two particles moving in the same

Question: Statement-1 : Two particles moving in the same direction do not lose all their energy in a completely inelastic collision. Statement-2 : Principle of conservation of momentum holds true for all kinds of collisions.Statement $-1$ is true, Statement $-2$ is falseStatement-1 is true, Statement-2 is true; Statement-2 is the correct explanation of Statement-1Statement $-1$ is true, Statement $-2$ is true; Statement $-2$ is not the correct explanation of Statement-1Statement $-1$ is false, S...

A parallel plate capacitor of capacitance 90 pF is connected to a battery of emf 20V.

Question: A parallel plate capacitor of capacitance $90 \mathrm{pF}$ is connected to a battery of emf $20 \mathrm{~V}$. If a dielectric material of dielectric constant $\mathrm{K}=\frac{5}{3}$ is inserted between the plates, the magnitude of the induced charge will be:-0.3 n C2.4 n C0.9 n C1.2 n CCorrect Option: , 4 Solution:...

In a common emitter amplifier circuit using an

Question: In a common emitter amplifier circuit using an $\mathrm{n}-\mathrm{p}-\mathrm{n}$ transistor, the phase difference between the input and the output voltages will be$135^{\circ}$$180^{\circ}$$45^{\circ}$$90^{\circ}$Correct Option: , 2 Solution: In common emitter amplifier circuit input and out put voltage are out of phase. When input voltage is increased then $\mathrm{i}_{\mathrm{b}}$ is increased, $\mathrm{i}_{\mathrm{c}}$ also increases so voltage drop across $\mathrm{R}_{\mathrm{c}}$...

Prove the following

Question: A capacitance of $2 \mu \mathrm{F}$ is required in an electrical circuit across a potential difference of $1.0 \mathrm{kV}$. A large number of $1 \mu \mathrm{F}$ capacitors are available which can withstand a potential difference of not more than $300 \mathrm{~V}$. The minimum number of capacitors required to achieve this is :2432216Correct Option: , 2 Solution:...

Identify the semiconductor devices whose characteristics are given below

Question: Identify the semiconductor devices whose characteristics are given below, in the order (a), (b), (c), (d) :- Zener diode, Solar cell, Simple diode, Light dependent resistanceSimple diode, Zener diode, Solar cell, Light dependent resistanceZener diode, Simple diode, Light dependent resistance, Solar cellSolar cell, Light dependent resistance, Zener diode, Simple diodeCorrect Option: , 2 Solution: Factual...

Three sound waves of equal amplitudes have frequencies

Question: Three sound waves of equal amplitudes have frequencies $(v-1), v,(v+1)$. They superpose to give beats. The number of beats produced per second will be :- 2143Correct Option: 1 Solution:...

The temperature dependence of resistances of

Question: The temperature dependence of resistances of $\mathrm{Cu}$ and undoped Si in the temperature range 300 $400 \mathrm{~K}$, is best described by :-Linear decrease for $\mathrm{Cu}$, linear decrease for Si.Linear increase for $\mathrm{Cu}$, linear increase for Si.Linear increase for $\mathrm{Cu}$, exponential increase for $\mathrm{Si}$Linear increase for $\mathrm{Cu}$, exponential decrease for $\mathrm{Si}$Correct Option: , 4 Solution: Factual $\mathrm{Cu}$ is conductor so with increase i...

Consider a rubber ball freely

Question: Consider a rubber ball freely falling from a height $\mathrm{h}=4.9 \mathrm{~m}$ onto a horizontal elastic plate. Assume that the duration of collision is negligible and the collision with the plate is totally elastic. Then the velocity as a function of time and the height as a function of time will be :-Correct Option: 1 Solution:...

The dimension of magnetic field in

Question: The dimension of magnetic field in $\mathrm{M}, \mathrm{L}, \mathrm{T}$ and $\mathrm{C}$ (Colulomb) is given as$\mathrm{MLT}^{-1} \mathrm{C}^{-1}$$\mathrm{MT}^{2} \mathrm{C}^{-2}$$\mathrm{MT}^{-1} \mathrm{C}^{-1}$$\mathrm{MT}^{-2} \mathrm{C}^{-1}$Correct Option: , 3 Solution:...

In the given circuit diagram when the current reaches steady state in the circuit,

Question: In the given circuit diagram when the current reaches steady state in the circuit, the charge on the capacitor of capacitance $\mathrm{C}$ will be :$\mathrm{CE} \frac{\mathrm{r}_{2}}{\left(\mathrm{r}+\mathrm{r}_{2}\right)}$$\mathrm{CE} \frac{r_{1}}{\left(r_{1}+r\right)}$CE$\mathrm{CE} \frac{\mathrm{r}_{1}}{\left(\mathrm{r}_{2}+\mathrm{r}\right)}$Correct Option: 1 Solution:...

Which of the following units denotes the dimensions

Question: Which of the following units denotes the dimensions $\left[\mathrm{ML}^{2} / \mathrm{Q}^{2}\right]$, where $\mathrm{Q}$ denotes the electric charge ?$\mathrm{Wb} / \mathrm{m}^{2}$henry (H)$\mathrm{H} / \mathrm{m}^{2}$weber (Wb)Correct Option: , 2 Solution:...

Out of the following pairs,

Question: Out of the following pairs, which one does not have identical dimensions?Angular momentum and Planck's constantImpulse and momentumMoment of inertia and moment of a forceWork and torqueCorrect Option: , 4 Solution:...

A combination of capacitors is set up as shown in the figure.

Question: A combination of capacitors is set up as shown in the figure. The magnitude of the electric field, due to a point charge $\mathrm{Q}$ (having a charge equal to the sum of the charges on the $4 \mu \mathrm{F}$ and $9 \mu \mathrm{F}$ capacitors), at a point $30 \mathrm{~m}$ from it , would equal: $480 \mathrm{~N} / \mathrm{C}$$240 \mathrm{~N} / \mathrm{C}$$360 \mathrm{~N} / \mathrm{C}$$420 \mathrm{~N} / \mathrm{C}$Correct Option: , 4 Solution:...

In the given circuit,

Question: In the given circuit, charge $\mathrm{Q}_{2}$ on the $2 \mu \mathrm{F}$ capacitor changes as $\mathrm{C}$ is varied from $1 \mu \mathrm{F}$ to $3 \mu \mathrm{F}$. $\mathrm{Q}_{2}$ as a function of ' $\mathrm{C}^{\prime}$ is given properly by : (figures are drawn schematically and are not to scale):- Correct Option: , 4 Solution:...

Which one of the following represents the correct dimensions

Question: Which one of the following represents the correct dimensions of the coefficient of viscosity?$\left[\mathrm{ML}^{-1} \mathrm{~T}^{-2}\right]$$\left[\mathrm{MLT}^{-1}\right]$$\left[\mathrm{ML}^{-1} \mathrm{~T}^{-1}\right]$$\left[\mathrm{ML}^{-2} \mathrm{~T}^{-2}\right]$Correct Option: , 3 Solution: $\mathrm{F}=\eta A \frac{\Delta v}{\Delta x}$, where $\mathrm{F}=$ force...

A parallel plate capacitor is made of two circular plates separated by a distance of

Question: A parallel plate capacitor is made of two circular plates separated by a distance of $5 \mathrm{~mm}$ and with a dielectriic of dielectric constant $2.2$ between them. When the electric field in the dielectric field in the dielectric is $3 \times 10^{4} \mathrm{~V} / \mathrm{m}$, the charge density of the positive plate will be close to :$3 \times 10^{4} \mathrm{C} / \mathrm{m}^{2}$$6 \times 10^{4} \mathrm{C} / \mathrm{m}^{2}$$6 \times 10^{-7} \mathrm{C} / \mathrm{m}^{2}$$3 \times 10^{...

Prove the following

Question: Two capacitors $\mathrm{C}_{1}$ and $\mathrm{C}_{2}$ are charged to $120 \mathrm{~V}$ and $200 \mathrm{~V}$ respectively. It is found that by connecting them together the potential on each one can be made zero. Then :$5 \mathrm{C}_{1}=3 \mathrm{C}_{2}$$3 \mathrm{C}_{1}=5 \mathrm{C}_{2}$$3 \mathrm{C}_{1}+5 \mathrm{C}_{2}=0$$9 C_{1}=4 C_{2}$Correct Option: , 2 Solution:...

Question: Two capacitors $\mathrm{C}_{1}$ and $\mathrm{C}_{2}$ are charged to $120 \mathrm{~V}$ and $200 \mathrm{~V}$ respectively. It is found that by connecting them together the potential on each one can be made zero. Then :$5 \mathrm{C}_{1}=3 \mathrm{C}_{2}$$3 \mathrm{C}_{1}=5 \mathrm{C}_{2}$$3 \mathrm{C}_{1}+5 \mathrm{C}_{2}=0$$9 C_{1}=4 C_{2}$Correct Option: , 2 Solution:...

The physical quantities not having same dimensions are :

Question: The physical quantities not having same dimensions are :torque and workmomentum and planck's constantstress and Young's modulusspeed and $\left(\mu_{0} \in_{0}\right)^{-1 / 2}$Correct Option: , 2 Solution:...

The figure shows an experimental plot for discharging of a capacitor in an R–C circuit.

Question: The figure shows an experimental plot for discharging of a capacitor in an $\mathrm{R}-\mathrm{C}$ circuit. The time constant $\tau$ of this circuit lies between:- $100 \mathrm{sec}$ and $150 \mathrm{sec}$$150 \mathrm{sec}$ and $200 \mathrm{sec}$0 and $50 \mathrm{sec}$$50 \mathrm{sec}$ and $100 \mathrm{sec}$Correct Option: 1 Solution:...