Explore topic-wise InterviewSolutions in .

A $1.00\times {10}^{-20}kg$ particle is vibrating with simple harmonic motion with a period of $1.00\times {10}^{-5}sec$ and a maximum speed of $1.00\times {10}^{3}m/s$. The maximum displacement of the particle is

A glass plate of length $10\text{cm}$, breadth $4\text{cm}$ and thickness $0.4\text{cm}$ weighs $20\text{g}$ in air. Half of the plate is immersed in water in such a way that its breadth is perpendicular to water. Calculate force due to surface tension and buoyant force of plate. Surface tension of water is $70\text{dyne/cm}$.

Velocity-time equation of a particle moving in a straight line is, $v=(2t+3t^2)$. Find displacement of particle from the origin at time $t=1\text{s}$, if it is given that displacement is $10\text{m}$ at time $t=0$

a train is moving towards east with a speed of 20m/s . A person is running on the roof of the train with a speed 3m/s against the motion of train . Velocity of the person as seen by an observer on ground will be-

Ans is 17m/s towards east..how?

A system of three polarizers $P_1,P_2,P_3$ is set up such that the pass axis of $P_3$, is crossed with respect to that of $P_1$. The pass axis of $P_2$ is inclined at ${60}^{\circ }$ to the pass axis of $P_3$. When a beam of unpolarized light, of intensity $I_0$, is incident on $P_1$, the intensity of light transmitted by the three polarizers is $I$. The ratio $\left(\frac{I_0}{I}\right)$ equals (nearly) :

A
circular coil of 20 turns and radius 10 cm is placed in a uniform
magnetic field of 0.10 T normal to the plane of the coil. If the
current in the coil is 5.0 A, what is the

(a)
total torque on the
coil,

(b)
total force on the coil,

(c)
average force on each
electron in the coil due to the magnetic field?

(The
coil is made of copper wire of cross-sectional area 10⁻⁵
m²,
and the free electron density in copper is given to be about 10²⁹
m⁻³.)

In $SI$ units, the dimensions of $\sqrt{\frac{{ϵ}_0}{{\mu }_0}}$ is

A particle is performing simple harmonic motion. At time ‘t’, its displacement from the mean position is x and its speed is v. The corresponding resultant force on it is F and its acceleration is a. At the same time, it has kinetic energy K and potential energy U.

The variation of kinetic energy (k) with displacement (x) is given by the graph

Ball 1 of mass $m$ moving at a speed $v$ makes a head-on collision with an identical ball 2 at rest. The kinetic energy of the balls after the collision is $\frac{3}{4}$th of original. If $e$ is the coefficient of restitution and $v_1,v_2$ are the velocities of the balls after collision, then:

A projectile thrown with an initial velocity $u$ has the same range R when the maximum height attained by it is either $h_1$ or $h_2.$ Then $R,h_1$ and $h_2$ are related as

Choose the correct statement. When the temperature of a gas is increased

R.M.S velocity of an ideal gas molecules is $300\text{m/s}$ at $1\text{atm}$ pressure. If pressure is increased to four times, then R.M.S velocity becomes

$($The density of gas remains same$.)$

A string of length L and mass M is lying on a horizontal table. A force F is applied at one of its ends. Tension in the string at a distance y from the end at which the force applied is:

Ifis
a nonzero vector of magnitude ‘a’ and λ
a nonzero scalar, then λis
unit vector if

(A) λ
= 1 (B) λ = –1 (C)

(D)

The stream of a river is following with a speed of $2\text{km/h}$. A swimmer can swim at a speed of $4\text{km/h}$. What should be the direction of swimmer with respect to the flow of the river to cross the river straight?

What are the main difference of glass, made up SiO4 tetrahedral ?

Acceptance angle $\left(\theta \right)$ for an optical fiber is defined as the maximum angle of incidence at the interface of medium (air usually) and core $(\mu =n_1)$ for which light ray enters and travel along the optical fiber. Sine of acceptance angle is known as numerical aperture of the optical fiber. Then in the given setup, what is the value of numerical aperture?

A block of mass $m$ is on an inclined plane of angle $\theta$. The coefficient of friction between the block and the plane is $\mu$ and $\tan \theta >\mu$. The block is held stationary by applying a force $P$ parallel to the plane. The direction of force pointing up the plane is taken to be positive. As $P$ is varied from $P_1=mg(\sin \theta -\mu \cos \theta )$ to $P_2=mg(\sin \theta +\mu \cos \theta )$, the frictional force $f$ versus $P$ graph will look like

If in the circuit, power dissipation is $150\text{W}$, then $R$ is

A bi-convex lens of glass $(n_g=\frac{3}{2})$ is immersed in water $(n_w=\frac{4}{3}).$ The ratio of new focal length of the lens to the focal length of lens in air is n. The value of n is:___

Two conducting rods A and B of same length and cross-sectional area are connected (i) In series (ii) In parallel as shown. In both combination a temperature difference of ${100}^{\circ }$ C​ is maintained. If thermal conductivity of A is 3K and that of B is K then the ratio of heat current flowing in parallel combination to that flowing in series combination is

A rifle shoots a bullet from the ground level with a muzzle velocity of $400m/s$ at a small target $400m$ away on the ground. The height above the target at which the bullet must be aimed to hit the target is
$(g=10m{s}^{-2})$

Air is pushed into a soap bubble of radius 'r' to double its radius. If the surface tension of the soap solution is S, the work done in the process is?

A block of mass $m$ is connected to another block of mass $M$ by a massless spring of spring constant $k$. The blocks are kept on a smooth horizontal plane. Initially the blocks are at rest and the spring is unstretched. Then a constant force $F$ starts acting on the block of mass $M$ to accelerate it. Find the force on the block of mass $m$.

A solid metallic cylinder carries a direct current. The magnetic field produced by it exists

Two blocks of masses $m_1$ and $m_2$ are connected by a light inextensible string which passes over a fixed pulley. Initially, mass $m_1$ moves with a velocity $v_0$ when the string is not taut. Neglect friction at all contact surfaces. Find the velocity of the blocks just after the string is taut, if $m_1=2\text{kg},m_2=3\text{kg}$ and $v_0=5\text{m/s}$

An aeroplane has to go along straight line from $A$ to $B$ and back along. The relative speed w.r.t. wind is $V$. The wind blows perpendicular to line $AB$ with speed $V_o$. The distance between $A$ & $B$ is $l$. The total time for the round trip is

Effective capacitance between A & B is

In the given series LCR circuit, the hot wire voltmeter whose reading will be zero at resonance, is -