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A 0.1 kg mass is suspended from a wire of negligible mass. The length of the wire is 1 m and its cross-sectional area is $4.9\times {10}^{-7}{m}^2.$ If the mass is pulled a little in the vertically downward direction and released, it performs simple harmonic motion of angular frequency $140rad{s}^{-1}$ . If the Young’s modulus of the material of the wire is n $\times {10}^{9}N{m}^{-2}$, find the value of n.

Two identical metal plates shown photoelectric effect by a light of wavelength λ_A falls on plate A and λ_B on plate B(λ_A = 2λ_B). The maximum kinetic energy is

A parallel beam of light of wavelength $6000\dot{A}$ is incident normally on a slit of width $0.2\text{mm}$. The diffraction pattern is observed on a screen which is placed at the focal plane of a convex lens of focal length $50\text{cm}$. If the lens is placed close to the slit. The distance between the minimum on both sides of the central maximum will be

1. 357.14

A steel rod of cross-sectional area $1{\text{m}}^2$ is acted upon by forces as shown in the figure. The total elongation of the bar is (Take $Y=2.0\times {10}^{11}{\text{Nm}}^{-2}$)

A time dependent force $F=p+q{t}^2$ acts on a particle of mass $3\text{kg}$. If the particle starts from rest, the work done by the force during the first $3$ second will be [$p$ and $q$ are $+ve$ constant]

For an isobaric process involving an ideal gas, the ratio of heat supplied and work done by the system (gas) is

Identify the incorrect statement regarding the reflection of light from a plane mirror when a light ray is incident obliquely. $\overrightarrow{R},\overrightarrow{I}$ and $\overrightarrow{N}$ represents the vectors along the reflected ray, incident ray and normal direction.

When light rays are incident on a prism at an angle of ${45}^{\circ }$, the minimum deviation is obtained. If refractive index of the material of prism is $\sqrt{2}$ then the angle of prism will be ​

Two submarines are approaching each other in a calm sea. The first submarine travels at a speed of 36 km $h^{-1}$ and the other at 54 km $h^{-1}$' relative to the water. The first submarine sends a sound signal (sound waves in water are also called sonar) at a frequency of 2000 Hz. (a) At what frequency is this signal received by the second submarine ? (b) The signal is reflected from the second submarine. At what frequency is this signal received by the first submarine. Take the speed of the sound wave in water to be $1500m{s}^{-1}$

A particle has initial velocity as $u_x$ i + $u_y$j and acceleration as -$a_y$. Find the maximum Y that it reaches?

A block of mass 5.0 kg slides down from the top of an inclined plane of length 3 m. The first 1 m of the plane is smooth and the next 2 m is rough. The block is released from rest and again comes to rest at the bottom of the plane. If the plane is inclined at ${30}^{\circ }$ with the horizontal, find the coefficient of friction on the rough portion.

A sphere of mass $M=2\text{kg}$ moving with a velocity of $2\sqrt{2}\text{m/s}$ collides with another sphere of mass $m=1\text{kg}$ initially at rest at an angle of ${45}^{\circ }$ with the horizontal. If the coefficient of restitution of the collision is 0.5, what will be the final velocity(in $\text{m/s}$) of the sphere having mass $m$ ?

A converging lens of focal length 15 cm and a converging mirror of focal length 20 cm are placed with their principal axes coinciding. A point source S is placed on the principal axis at a distance of 12 cm from the lens as shown in figure It is found that the final beam comes out parallel to the principal axis. Find the separation between the mirror and the lens.

The tungsten filament of an electric lamp has a length of $0.5\text{m}$ and a diameter $6\times {10}^{-5}\text{m}$. The power rating of the lamp is $60\text{W}$. Assuming the radiation from the filament is equivalent to 80% of a perfect black body radiator at the same temperature, estimate the steady state temperature of the filament (Stefan's constant $=5.7\times {10}^{-8}{\text{W m}}^{-2}{\text{K}}^{-4}$)

When forces $F_1$, $F_2$, $F_3$ are acting on a particle of mass m such that $F_2$ and $F_3$ are mutually perpendicular, then the particle remains stationary. If the force $F_1$ is now removed then the magnitude acceleration of the particle is:
(AIEEE-2002)

Potential energy of the electron at infinity is equal to

Three thin rods each of length $L$ and mass $M$ are placed along $X,Y$ and $Z$ axes in such a way that one end of each rod is at the origin as shown. The moment of inertia of this system about $Z-$ axis is

The difference between the apparent frequencies of a source of sound as perceived by a stationary observer during its approach and recession is 2% of the actual frequency of the source. If the speed of sound is 300 m/s, the speed of source is

A salient pole alternator has $X_d=1.5p.u.,X_q=0.80p.u.$ If this alternator is supplying rated kVA at unity power factor to infinite bus and infinite bus voltage is 1.0 p.u., then power angle will be

The total pressure exerted by a mixture of 4g of $O_2$ and 2g of $H_2$ confined in a bulb of 1 L at $O^{\circ }$ is –

A convex spherical refracting surface of radius $R$ separates a medium having refractive index $2.5$ from a medium having refractive index $1.5$. As an object $\left(O\right)$ is moved towards the surface, from a point far away from the surface as shown in the figure, along the central axis, its image changes from real to virtual when it is at a distance $x$ from the pole $P$ of the surface. Find $x$.

Distance equals speed × ______.

A force $F=-K(yi+aj)$ (where K is a positive constant) acts on a particle moving in the xy-plane. Starting from the origin, the particle is taken along the positive x-axis to the point (a, 0) and then parallel to the y-axis to the point (a, a). The total work done by the force F on the particles is

The
Marina trench is located in the Pacific Ocean, and at one place it is
nearly eleven km beneath the surface of water. The water pressure at
the bottom of the trench is about 1.1 × 10⁸
Pa. A steel ball of initial volume 0.32 m³
is dropped into the ocean and
falls to the bottom of the trench. What is the change in the volume
of the ball when it reaches to the bottom?

The rate of radiation of a black body at $0^0$ C is EJ/sec. The rate of radiation of this black body at ${273}^0$ C will be

A body Falls vertically from the height H=19.6m with its initial velocity equal to zero what time will it take to travel

1 The first metre .

2 The last meter.

Please answer the question in detail?

And please don't copy it from Google.

A band playing music at frequency f is moving towards a wall at a speed $v_b$. A motorist is following the band with a speed $v_m$. If v is the speed of sound, the expression for the beat frequency heard by the motorist is