Explore topic-wise InterviewSolutions in .

A spherical capacitor consists of an inner sphere of radius $12\text{cm}$ and the outer sphere of radius $36\text{cm}$. The capacitance is $C_1$ when the inner sphere is charged and the outer sphere is earthed and $C_2$ when the inner sphere is earthed and outer sphere is charged. The ratio $\frac{C_1}{C_2}$ is

The following figure shows tracks of three charged particles in a uniform electrostatic field. Give the signs of the three charges. Which particle has the highest charge-to-mass ratio?

A storage battery of
emf 8.0 V and internal resistance 0.5 Ω is being charged by a
120 V dc supply using a series resistor of 15.5 Ω. What is the
terminal voltage of the battery during charging? What is the purpose
of having a series resistor in the charging circuit?

Electric field $\overrightarrow{E}=4t\hat{i}$ exists in space. Displacement current associated with a square of side a = 2cm with its plane perpendicular to $\overrightarrow{\epsilon }$ at t = 2 sec will be

The figure shows two long parallel current carrying wires separated by a distance $5\text{m}$. The magnetic field at a point $\text{P}$, situated midway between the two wires will be

Gravel is dropped into a conveyor belt at the rate of $0.5\text{Kg/s}$. Find the extra force required to keep the belt moving at $2\text{m/s}$.

Match the electronic configurations of the elements given in List - I with their correct characteristic(s) (i.e., properties for given configuration) given in List - II.

$\begin{array}{cccc}& \text{List-I}& & \text{List - II}\\ \text{P.}& 1s^2& 1.& \text{Element shows highest negative oxidation state}\\ \text{Q.}& 1s^{2}2s^{2}2p^5& 2.& \text{Element shows highest first ionisation enthalpy}\\ \text{R.}& 1s^{2}2s^{2}2p^{6}3s^{2}3p^5& 3.& \text{Element shows highest electronegativity on Pauling scale}\\ \text{S.}& 1s^{2}2s^{2}2p^2& 4.& \text{Element shows maximum electron gain enthalpy (most exothermic)}\end{array}$

A man standing on a road has to hold his umbrella at ${30}^{\circ }$ with the vertical to keep the rain away. He then throws the umbrella and starts running at $10\text{km/h}$. He finds that rain drops are hitting his head vertically. Find the speed of rain with respect to road.

Four identical rods $\text{AB, CD. CF}$ and $\text{DR}$ are joined as shown in figure. The length, cross-sectional area and thermal conductivity of each rod are $l,A$ and $K$ respectively. The ends $\text{A, E}$ and $\text{F}$ are maintained at temperatures $T_1={70}^{\circ }\text{C},T_2={30}^{\circ }\text{C}$ and $T_3={40}^{\circ }\text{C}$ respectively. Assuming no loss of heat to the atmosphere, find the temperature at $\text{B}$.

If three particles, each of mass $M$, are placed at the three corners of an equilateral triangle of side $a$, the forces exerted by this system on another particle of mass $M$ placed

$\left(i\right)$ at the midpoint of a side and

$\left(ii\right)$ at the centre of the triangle are respectively,

The value of acceleration due to gravity at certain height $h$ above the surface of the earth is $\frac{g}{4}$ , where $g$ is the value of acceleration due to gravity at the surface of the earth. The height $h$ is ($R$ is the radius of earth)

Question 5 (a)

What is the highest total resistance that can be secured by combinations of four coils of resistance $4\Omega ,8\Omega ,12\Omega$ and $24\Omega$?

The temperature at which the r.m.s. speed of $O_2$ is equal to that of neon at 300 K is:
(atomic mass of $O_2$ = 32 u and Ne = 20 u)

A block of mass $2\text{kg}$ connected to a spring of spring constant $8{\text{Nm}}^{–1}$ is allowed to oscillate on a rough horizontal surface. If the system experiences a damping force $=0.230\times$ velocity, then the time required for the amplitude of resulting oscillation to fall to half of its initial value is

The maximum range for a shell fired by a cannon on horizontal terrain is $20\text{km}$. What must be the muzzle velocity of the shell? (Take $g=10{\text{m/s}}^2$)

A vessel contains 14 g of hydrogen and 96 g of oxygen at STP. Chemical reaction is induced by passing electric spark in the vessel till one of the gases is consumed. The temperature is brought back to its starting value 273 K. Find the pressure in the vessel.

The track shown in figure is frictionless. The block $B$ of mass $2m$ is lying at rest and the block $A$ of mass $m$ is pushed along the track with some speed. The collision between $A$ and $B$ is perfectly elastic. With what velocity should the block $A$ be started to get the sleeping man awakened?

The displacement x of a particle moving in one dimension under the action of a constant force is related to the time t by the equation, t = $\sqrt{x}$ + 3 where x is in meters and t is in seconds. The work done by the force in the first 6 seconds is

The particles are separated at a horizontal distance $x$ as shown in the figure. They are projected at the same time as shown in the figure with different initial speeds. The time after which the horizontal distance between the particles become zero is

Three identical particles $\text{A},\text{B}$ and $\text{C}$ are joined together by a thread as shown in figure. All the particles are moving in a horizontal plane around point $O$. If the velocity of the outermost particle is $v_0$ then the ratio of tensions in the three sections of the string is

Three resistances of magnitude $R$ each are connected in the form of an equilateral triangle of side $a$. The combination is placed in a magnetic field $B=B_0{e}^{-\lambda t}$ perpendicular to the plane. The induced current in the circuit is given by

A billiard ball is hit from a point on the vertical board of the table close to the pocket D as shown in the figure. It meets the horizontal board at an angle of 45⁰, and continues following the arrow. Into which pocket will the ball fall?

Two
billiard balls each of mass 0.05 kg moving in opposite directions
with speed 6 m
s^–1
collide and rebound with the same speed. What is the impulse imparted
to each ball due to the other?

A hemispherical bowl just floats without sinking in a liquid of density 1.2 $\times$ ${10}^{3}kg/m^3$. If outer diameter and the density of the bowl are 1 m and 2 $\times$ 10${}^4$ kg/m${}^3$ respectively, then the inner diameter of the bowl will be

If a ball is thrown vertically upwards with speed u, the distance covered during the last t seconds of its ascent is

An electric iron of resistance $20\Omega$ takes a current of 5 A. Calculate the heat developed in 30 s.

If Rajesh moves along a circular path from point $A(0,0)$ as shown in the figure and reaches diametrically opposite point $B(10,0)$, what is his displacement vector? Given: radius of circle is $5\text{m}$.

In the given figure an L-shaped bar of mass $M$ is pivoted at one of its end, so that it can freely rotate in a vertical plane. Find the frequency of oscillation, if it is slightly disturbed from its equilibrium position.

Why does not electron falls into the nucleus when it is rotating around the nucleus as their is electrostatic force is acting (I want a simpler answer)

A radio transmitter operates at a frequency of 880 kHz and a power of 10 kW. The number of photons emitted per second are