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A light wave of wavelength $\lambda$ is incident on a slit of width d. The resulting diffraction pattern is observed on a screen at a distance of D. If the linear width of the principal maxima is equal to the width of the slit, then the distance D is

A) $\frac{2\lambda}{d}$

B) $\frac{d^{2}}{2\lambda}$

C) $\frac{2\lambda^{2}}{d}$

D) $\frac{d^{}}{\lambda}$

An obstacle is moving towards the source with velocity v. The sound is reflected from the obstacle. If c is the speed of sound and $\lambda$ is the wavelength, then the wavelength of the reflected wave, $\lambda_{r}$is

A) $\lambda_{r}=\left(\frac{C-V}{C+V}\right)\lambda$

B) $\lambda_{r}=\left(\frac{C+V}{C-V}\right)\lambda$

C) $\lambda_{r}=\left(\frac{C-V}{C}\right)\lambda$

D) $\lambda_{r}=\left(\frac{C+V}{C}\right)\lambda$

In a communication system, a repeater is used to extend the range to transmission. It is the combination of

A) IF stage and amplifier

B) rectifier and detector

C) recevier and transmitter

D) modulator and power amplifier

A large open tank containing water has two holes to its wall. A square hole of side a is made at a depth of y and a circular hole of radius r is made at a depth of 16 y from the surface of the water. If an equal amount of water comes out through both the holes per second, then the relation between r and a will be

A) $r=\frac{a}{2\sqrt{\pi}}$

B) $r=\frac{a}{2\pi}$

C) $r=\frac{2a}{\pi}$

D) $r=\frac{2a}{\sqrt{\pi}}$

A spherical rubber balloon carries a charge, uniformly distributed over the surface. As the balloon is blown up and increase in size. The total electric flux coming out of the surface

A) increases

B) remains unchanged

C) becomes zero

D) decreases

Five capacitors each of capacity C are connected as shown in the figure. If their resultant capacity is 2 $\mu$ F, then the capacity of each condenser is

A) 5 $\mu$ F

B) 2 $\mu$ F

C) 2.5 $\mu$ F

D) 10 $\mu$ F

In conversion of moving coil galvanometer into an ammeter of required range, the resistance of ammeter , so formed is

[ S= shunt and G= resistance of galvanometer]

A) $\frac{S+G}{SG}$

B) $\frac{SG}{S+G}$

C) $\frac{S-G}{SG}$

D) $\frac{SG}{S-G}$

In the system of two particles of masses m₁ and m₂, the first particle is moved by a distance d towards the centre of mass.To keep the centre of mass unchanged, the second particle will have to be moved by a distance

A) $\frac{m_{2}}{m_{1}}d,$ towards the centre of mass

B) $\frac{m_{1}}{m_{2}}d,$ away fron the centre of mass

C) $\frac{m_{1}}{m_{2}}d,$ towards the centre of mass

D) $\frac{m_{2}}{m_{1}}d,$ away from the centre of mass

The graph of stopping potential V_s against frequency v of incident radiation is plotted for two different metals P and Q as shown in the graph, $\phi_{P}$ and $\phi_{Q}$ are work-functions of P and Q respectively, then

A) $\phi_{P} > \phi_{Q}$

B) $\phi_{P} < \phi_{Q}$

C) $\phi_{P} = \phi_{Q}$

D) $v_{0} ' < v_{0}$

If the maximum kinetic energy of emitted electrons in photoelectric effect is 3.2 x 10^-19 J and the work-function for metal is

6.63 x10^-19J, then stopping potential and threshold wavelength respectively are

[Planck's constant,h=6.63 x10³⁴ J-s]

[ Velocity of light , c=3 x10⁸ m/s]

[charge on electron =1.6 x10^-19 C]

A) 4 V,6000 Å

B) 3V, 4000 Å

C) 2 V,3000 Å

D) 1 V,1000 Å

Water rises up to a height h in a capillary tube on the surface of the earth. The value of h will increases if the experimental setup is kept in [ g=acceleration due to gravity]

A) a lift going upward with a certain acceleration

B) accelerating train

C) a satellite rotating close to earth

D) a lift going down with acceleration a < g

Two cells having unknown emf E₁and E₂ (E₁ > E₂) are connected in a potentiometer circuit,to assist each other. The null point obtained is at 490 cm from the higher potential end. When cell E₂ is connected, so as to oppose cell E₁, the null point is obtained at 90 cm from the same end, the ratio of the EMFs of two cells $\left(\frac{E_{1}}{E_{2}}\right)$ is

A) 0.689

B) 5.33

C) 1.45

D) 0.182

The angle subtended by the vector $A=4\hat{i}+3\hat{j}+12\hat{k}$ with the X-axis is

A) $\cos^{-1}\left(\frac{3}{13}\right)$

B) $\sin^{-1}\left(\frac{3}{13}\right)$

C) $\sin^{-1}\left(\frac{4}{13}\right)$

D) $\cos^{-1}\left(\frac{4}{13}\right)$

Two bodies A and B of equal mass are suspended from two separate massless springs of force constant k₁ and k₂, respectively. The bodies oscillate vertically such that their maximum velocities are equal. The ratio of the amplitudes of body A to that of body B is

A) $\sqrt{\frac{k_{2}}{k_{1}}}$

B) $\frac{k_{2}}{k_{1}}$

C) $\frac{k_{1}}{k_{2}}$

D) $\sqrt{\frac{k_{1}}{k_{2}}}$

A body of mass 64 g is made to oscillate turn by turn on two different springs A and B. spring A and B has a force constant 4$\frac{N}{m}$ and 16 $\frac{N}{m}$ respectively. If T₁ and T₂ are period of oscillations of spring A and B respectively , Then $\frac{T_{1}+T_{2}}{T_{1}-T_{2}}$ will be

A) 1:2

B) 1:3

C) 3:1

D) 2:1

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