Explore topic-wise InterviewSolutions in Current Affairs.

An object 60 cm from a lens gives a virtual image at a distance of 20 cm in front of the lens. What is the focal length of the lens ? Is the lens converging or diverging ? Give reasons for your answer.

Calculate the displacement of a ball of mass of 20 g in 5 seconds if a force of 0.5 N acts on it when it is at rest for 5 seconds. Also calculate the velocity of the ball at the end of 5 seconds.

Five resistors of different resistances are connected together as shown in the figure. A 12 V battery is connected to the arrangement. The total resistance in the circuit is:

What do you understand by the clockwise and anticlockwise moment of force? When is it taken positive?

What will be used for the development of biological computers?

You have a metal wire of length $1000m$, a radius of $0.7mm$ and resistivity of the metal is given as $153.86\times {10}^{-6}\Omega$-m. Find the resistance of the wire.

You are given three resistances of 1, 2 and 3 ohms. Show by diagrams how with the help of these resistances you can get:
$\left(i\right)6\Omega \left(ii\right)\frac{6}{11}\Omega \left(iii\right)1.5\Omega$

A mirror forms diminished, real and inverted image. Choose the type of mirror and position of object in front of it to obtain such an image.

In a three-pin plug, the pin made longer and thicker than the other two pins is

Which part of the solar cooker is responsible for green house effect in it?

When we enter a dark room, what happens to the size of the pupil?

The phenomenon of electromagnetic induction is _____.

What is the direction of magnetic field at the centre of a coil carrying current in (i) the clockwise, (ii) the anticlockwise, direction?

In a hydroelectric power plant more electrical power can be generated if water falls from a greater height. Why?

In an experiment, 17 g of ice is used to bring down the temperature of 40 g of water at ${34}^{\circ }C$ to its freezing temperature. The specific heat capacity of water is 4.2 J $g^{-1}{K}^{-1}$. Calculate the specific latent heat of ice. State one important assumption made in the above calculation.

In which direction the force must be applied, when a single pulley is used with a mechanical advantage greater than one?

The technique that uses ultrasonic waves to measure the distance, direction and speed of underwater objects?

Kepler's second law states that the straight line joining the planet to the sun sweeps out equal areas in equal time. The statement is equivalent to saying that:

the current through 20 ohm resistor.

input audio signal is given below. which of the following can be amplified audio signal

What is magnification in the below diagram?

If OA = 10 cm and $O^{{}^{\prime }}$$A^{{}^{\prime }}$ = 2 cm?

Differentiate between the properties of virtual and real images? How would you form each one of them? [5 MARKS]

Is there any difference between the refractive index of ice & water ?

___ is the form of energy that produces a feeling of hotness.

Why should we measure dispersion for some particular value?

Define the term potential difference?

540 g of ice at $0^{\circ }C$ is mixed with 540 g of water at ${80}^{\circ }C$. The final temperature of the mixture is

What is electric charge?

What is special theory of relativity? What kind of things does it tells about electromagnetism? And how electricity and magnetism are two face of same coin by special theory of relativity?

The cells which derive electrical energy from chemical action are called __ cells.

Draw ray diagrams to represent the nature, position and relative size of the image formed by a convex lens for the object placed : (a) at $2F_1$, (b) between $F_1$ and the optical centre O of the lens. Which of the above two cases shows the use of the convex lens as a magnifying glass ? Give reasons for your choice.

Choose the correct option:

$$\begin{array}{cccc}1.& \text{Tone}& \text{i.}& \text{frequencies that are integral multiple of fundamental frequency.}\\ 2.& \text{Note}& \text{ii.}& \text{sound of single frequency.}\\ 3.& \text{Overtone}& \text{iii.}& \text{sound of multiple frequencies.}\\ 4.& \text{Harmonic}& \text{iv.}& \text{higher frequencies other than fundamental frequency.}\end{array}$$

(a) An extended object in the form of an arrow pointing upward has been placed in front of a plane mirror. Draw a labelled ray-diagram to show the formation of its image. (b) State the uses of plane mirrors.

Name the type of energy possessed by the bob of a simple pendulum when it is at (a) the extreme position,(b) the mean position, and (c) between the mean and extreme positions.

A block of mass 250kg falling at the rate of 10m in 5s is used to lift a load of 5000N by 2m in the same time. Calculate i) VR and ii) MA. Take g = 10m/s²

The sky at noon appears white. Give reason.

In the formula, $2n^2$ for finding the maximum number of electrons in an orbit, what does the letter 'n' represent?

The main constituent of petroleum gas is :
(a) methane (b) ethane (c) butane (d) propane

Explain total internal reflection.

A body of mass 2 kg is dropped from a building of height 5 m from the ground. The maximum kinetic energy the body can attain is: (Assume $g=10m/s^2$)

The boiling point of a liquid is decreased by

You have $mkgs$ of a certain liquid in a vessel, which is heated till there is a temperature change of $\Delta T$. If the coefficient of volume expansion is $\gamma$, what is the density of the liquid after heating, if the initial density was $\rho$?

The electrical appliances in a house are connected in :

(a) series

(b) parallel

(c) either in series of parallel

(d) both in series and parallel.

What would have been the colour of the sky if there had not been any atmosphere around the earth?

Name the material used for (i) filament of an electric bulb,, and (ii) heating element of a room heater.