Explore topic-wise InterviewSolutions in Current Affairs.

What is the dimension of the physical quantity$\left(\alpha \right)$ in the equation, $P=\frac{\text{density}}{\alpha }$, where $P$ is the pressure ?

A filament bulb $\left(500\text{W}100\text{V}\right)$ is to be wed in a $230\text{V}$ main supply. When a resistance $R$ is connected in series, it works perfectly and the bulb consumes $500\text{W}$. The value $R$ is

Kirchhoff’s current and voltage law are based on:

Same amount of heat is supplied to two liquids A and B. The liquid A shows a greater rise in temperature. What can you say about the heat capacity of A as compared to that of B ?

A convex lens is in contact with a concave lens. The magnitude of the ratio of their focal lengths is $\frac{2}{3}$. Their equivalent focal length is $30\text{cm}.$ What are their individual focal length? (in $\text{cm}$)

The lever for which the mechanical advantage is less than 1 has the :

(a) fulcrum at the midpoint between the load and effort.

(b) load between the effort and fulcrum.

(c) the effort between the fulcrum and load.

(d) load and effort acting at the same point.

A human body has a surface area of approximately $1m^2$. The normal body temperature is $10K$ above the surrounding room temperature $T_0$. Take the room temperature to he $T_0=300K$. For $T_0=300K$ the value of $\sigma T_0^4=460W{m}^{-2}$ (where $\sigma$ is the Stefan-Boltzmann constant). Which of the following options is/are correct?

Two stones lying on the surface of the Earth have mass, a gravitational force will always exist between them and it will try to pull the stones towards each other. But actually, we don’t see the stones moving towards each other, why?

Statement 1: The acceleration because of gravitational force is in the range of ${10}^{-12}$ $m{s}^{-2}$.

Statement 2: Stones are lying on a flat surface, so they cannot move.

Statement 3: The force of friction is much higher than the gravitational force.

Statement 4: The stones are irregular in shape, so they cannot move.

Which statements explains the reason for the above question?

An object is approaching a thin convex lens of focal length $0.3\text{m}$ with a speed of $0.01\text{m/s}$. The magnitude of the rate of change of position of image when the object is at a distance of $0.4\text{m}$ from the lens is

The magnetic potential energy stored in a certain inductor is $25\text{mJ}$, When the current in the inductor is $60\text{mA}$ This inductor is of inductance-

Which ray is negatively charged?

Where do magnetic field lines intersect ?

Suppose you are in an empty room which only contains UV-light. Will you be able to see walls? What is the range of wavelength of light we can see?

A block of ice at $-{10}^{\circ }C$ is slowly heated and converted to steam at ${100}^{\circ }C$. Which of the following curves represents the phenomenon qualitatively?

A metal conductor of length $1\text{m}$ rotates vertically about one of its ends at angular velocity $5\text{rad/sec}$. If the horizontal component of earth's magnetic field is $0.2\times {10}^{-4}\text{T}$, then the emf developed between the two ends of the conductor is

When the distance of the wire increases,then will it affect the potential difference, since work=f*s?

Why does a ray of light bend when it travels from one medium to another ?

State Avagadro’s Law.

A ray of light is incident on a plane mirror, i being the angle of incidence. What is the deviation suffered by the ray of light? [1 MARK]

(a) How does the resistance of a pure metal change if its temperature decreases?
(b) How does the presence of impurities in a metal affect its resistance?

The resolving power of human eye is

A short bar magnet passes at a steady speed right through a long solenoid. A galvanometer is connected across the solenoid. Which graph best represents the variation of the galvanometer deflection $\theta$ with time?

What is the conventional direction of electric current? How does it differ from the direction of flow of electrons?

A prism having refractive index $\mu =1.53$ is placed in water having refractive index $\mu =1.33$. If the angle of prism is ${60}^{\circ }$. Calculate the angle of minimum deviation in water.

$(\sin {35.1}^{\circ }=0.575)$

Question 28

Describe the activity that shows that a current-carrying conductor experiences a force perpendicular to its length and the external magnetic field. How does Fleming’s left-hand rule help us to find the direction of the force acting on the current carrying conductor?

Which of the following is not an effect of the indiscriminate exploitation of resources?

A glass prism with a refracting angle of ${60}^{\circ }$ has a refractive index $1.52$ for red and $1.6$ for violet light. A beam of white light is incident on one face at an angle of incidence, which gives minimum deviation for red light. If the angle of incidence is ${50}^{\circ }$ and minimum deviation for red light is ${40}^{\circ }$, find the angular dispersion of the spectrum.

[Given: $\sin \left({50}^{\circ }\right)=0.760,\sin \left({31.6}^{\circ }\right)=0.520,\sin \left({28.4}^{\circ }\right)=0.475,\sin {56}^{\circ }=0.832,\pi =\frac{22}{7}$]