Explore topic-wise InterviewSolutions in Current Affairs.

This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

1.

a satellite is orbiting the earth with speed v 0 .To make the satellite escape,what should be the minimum % increase in its velocity?

Answer»

Type your question

student-name Salini MUKHERJEE asked in Physics

a satellite is orbiting the earth with speed v0.To make the satellite escape,what should be the minimum % increase in its velocity?


Share 1 FOLLOW 1

student-name Neha Sarin answered this

409 helpful votes in Physics, Class XII-Science

we know that


orbital velocity


vo= √(g.r)


escape velocity


ve = √(2g.r)


thus, the increase in velocity WOULD be


dv = ve - vo = √(2g.r) - √(g.r)


or


dv = (√2 - √1).√(g.r)


so,


dv = 0.414√(g.r)


now,


the percentage increse would be


% dv = [(ve - vo) / vo ] x 100


= (dv / vo) x 100


or


= [0.414√(g.r) / √(g.r)] x 100


so, we get


% dv = 0.414 x 100 = 41.4%

2.

If 45n force is exterted on the area of 2cm square of an object then the the pressure is

Answer»

Heyy here is ur ans...

Pa = thrust/area

Area = 2cm^2 = 2/100×100m

Pa = 45/2/100×100

Pa = 45 × 100 × 100 / 2

Pa = 50 × 100 × 45

Pa = 5000 × 45

Pa = 225000pascals..

hope it helps u....THANKS...!!!

3.

A coil of inductance 8.4 mh and resistance 6 ? Is connected to a 12 v battery. The current in the coil is 1a at approximate time

Answer»

Here is UR ANSWER... FRIEND

4.

What is kienetic energy?

Answer»

Hey!!

here is your ANSWER ✍✍✍

Kinetic energy is the energy an object has because of its motion.

hope u GOT your answer ☺☺☺

5.

How much will be angular momentum of electron revolving in nth orbit?

Answer»

Hola User__________________

Here is Your Answer..!!!
___________________________

⭐Actually welcome to the concept of the MODERN PHYSICS..

⭐Basically According to the Bohrs Model of atom ...

⭐The second Postulate states that...

⭐The Angular momentum of the ELECTRON In nth orbit is given as the n times integral MULTIPLE of the nh/2pi


⭐Thus we can say that...

⭐L = nh/2 pi

⭐thus this implies ..

⭐mvr = nh/2 pi

____________________________

Hope it HELPS u...l☺

6.

Difference between optical pumping and electrical pumping

Answer»

Both optical pumping and electric pumping ate methods for population inversion.

# Optical pumping:
In this, the population inversion is achieved by means of light energy DELIVERED from APPROPRIATE pumping source such as gaseous discharge or flash TUBES. For example, in ruby laser, xenon flash tube is used.

# Electric pumping-
This type of pumping accomplished by means of intense electrical discharge in the MEDIUM and is particularly suited to gas media like He-Ne laser and CO2 laser. The electric discharge coverts the gas into a plasma where ACTIVE centers collide inelastically with free electrons and population inversion is achieved.

Hope i cleared your doubts...

7.

Please answer these two questions.

Answer»

In 20 the correct OPTION is D as for work DONE over an inclined PLANE the FORMULA is MG(sin theeta + mewcos theeta)

8.

What is the answer of question 22?

Answer» ANSWER of the QUESTION is KINETIC ENERGY
9.

What is the answer of question 27

Answer»

I THINK you are ANSWER is

C

10.

Why are the tools heated before fixing wooden handles ???

Answer»

Metal tools are HEATED to expend the opening where the handle is inserted . once heated, the handle is inserted and the metal CONTRACTS to MAKE a tight FIT keeps the head from FLYING off and punching through the windshield.

11.

Find the energy in kWh consumed in 10 hrs by four devices of power 500 W each

Answer»

Answer:

Known Terms:-

KWh = KILOWATT hour

W =  Watt

Given:-

Power consumed by four device = 500 W = \frac{500}{1000} = 0.5 kW

Time taken to consume the devices = 10 hours

To FIND:-

Energy consumed.

Formula to be used:-

Power = Energy/Time

Solution:-

Power = Energy/Time

Energy = Power × Time

Putting all the values, we get

Energy = 0.5 × 10

Energy = 5 kWh

Energy consumed by four devices

= 4 × 5

= 20 KWh or (20 units)

HENCE, Energy in kWh consumed in 10 hrs by four devices is 20 KWh

12.

Find odd one and explain among mass, weight, gravitional acceleration, gravitional force

Answer»

little addition to the above answer. gravitation ACCELERATION is GRAVITATIONAL force and WEIGHT are all the same.mass is constant for an object . the other THREE factors varies from place to place. mass the odd one out

13.

a straight copper conductor whose ends are connected to a sensitive galvanometer is moved up and down in a strong magnetic feild. what is your observation? what is the nature of current generated oin the conductor? what kind of energy transformation takes place in the above expreriment? name the device which works on the above principle and state the rule to find the direction of current induced in the conductor

Answer» DIRECTION is INDUCED TOWARDS rightFaraday LAW,
14.

What is the answer ...... it's urgent

Answer»

Answer is 5 times

Because we have to CHANGE direction the NUMBER of CORNERS in it

15.

The critical angle of a transparent crystal for greeen light is 30 degree .find the angle of polarisation of that crystal?

Answer»

We know, RELATION between polarising ANGLE and CRITICAL angle.
e.g., \boxed{\bf{tani=\frac{1}{sinC}}}

Where i is angle of polarisation and C is the critical and of the TRANSPARENT crystal.

so, tani = 1/sin30° = 1/(1/2) = 2
i = tan^-1(2)

hence, angle of polarisation is tan^-1(2)

16.

What is the subjective property of sound related to frequency and intensity...

Answer»

The SUBJECTIVE PROPERTY of SOUND related to its frequency is. The subjective property of sound related to its frequency is Pitch. Pitch is that characteristic of sound by which an acute or a shrill note can be distinguished from a grave or a FLAT note.

17.

Define the true bearing and magnetic bearing.

Answer»

Magnetic bearing: using magnetic compass readings to navigate from beginning to end points on the Earth’s SURFACE. magnetic compass readings show the user where the magnetic poles are in relation to their own location at a certain time and show that using minutes and seconds of arc. but the North and South Magnetic poles on a map are not located at the VERTICAL axes.

“True bearing” refers to the geometric lines which also define loci on the surface of the earth and are thought of as “true” because they never move like the Magnetic Poles and because the North and South Geographical poles are PRECISELY opposite “points” on the SPHERICAL Earth.

hope its helpfull BRAINLIEST please

18.

Two balls hanging from a pendulum of the same length go back to position 0.8

Answer»

its TRUE TWO BALLS hanging from a PENDULUM of the same length go back to POSITION 0.8

19.

Lakshmi gives a statement "CO and Co both represent elements ".is it correct?state reason.

Answer» HEY there!☺️


No ,. CO is a GAS CARBON monoxide which is MADE up of Carbon and oxygen.


While, Co is an element named Cobalt


Thanks
20.

A solid sphere of radius r/2 is cut out of a solid sphere of radius r such that the spherical cavity so formed touches the surface on one side and the centre of the sphere on the other side, as shown . The initial mass of the solid sphere was m. If a particle of mass m is placed at a distance 2.5r from the centre of the cavity, then what is the gravitational attraction on the mass m ?

Answer» GRAVITATIONAL FORCE of ATTRACTION
21.

A two slit Young's interference experiment is done with monochromatic light of wavelength 6000 A. The slits are 2 mm apart. The fringes are observed on a screen placed 10 cm away from the slits. Now a transparent plate of thickness 0.5 mm is placed in front of one of the slits and it is found that the interference pattern shifts by 5 mm . The refractive index of the transparent plate is(A) 1.2(B) 0.6(C) 2.4(D) 1.5

Answer»

Hey there....


I am here to answer you .

check out the pic and get your answer with an APPROPRIATE solution my dear...

hope it will be HELPFUL for you...

GLAD to help you...

I am in CLASS 11th..
and that's a question of class 12TH..pls mark as brainliest.


22.

What is mean by work?

Answer»

Work, in physics, MEASURE of energy TRANSFER that occurs when an object is moved over a DISTANCE by an external force at least part of which is applied in the DIRECTION of the displacement.

23.

Should the speed of two artificial satellite of the earth having different masses but the same orbital radius be the same

Answer»

⭐⭐Hey mate!⭐⭐


✍️__________________________________________________________


Near the orbit at


H~0


Orbital velocity = V√Gme/Re


Hence,


V1/V2 = √r2/r1


It there R from EARTH is also EQUAL..


Then,


Then


V1 =V2


Hope it will help you...


#PHOENIX



24.

What is natural and artificial satellite?

Answer» NATURAL satellite is moon


artificial satellites LIKE rohini, bhaskara ETC.
25.

Define Energy and also the different forms of energy. In Physics.

Answer»

Hi

Energy : Energy is the capacity for doing WORK .

The different froms of energy are as FOLLOWS :


POTENTIAL energy

Kinetic energy

Thermal energy

ELECTRICAL energy

Chemical energy

Nuclear energy


Energy can neither be created nor be destroyed. it can only change into ONE form to another form.

26.

Solve this:Q. A particle is projected vertically upward with speed u = 10 m/s. During its journey air applies a force of —0.2v2 on the particle. What is the maximum height attained by the particle [m=2kg] ? ​(1) 5 ln(2) ​ (2) 3 ln(2) (3) 2 ln(2)​ (4) 10 ln(2) ​

Answer»

(1) 5 In, it's UR ANSWER ? I HOPE it

27.

A diffraction pattern is obtained using a red light beam,what happens when red light replaced by blue light

Answer»

If the red LIGHT REPLACED by blue light then the DIFFRACTION band becomes NARROWER and CROWDED together because the diffraction band depends on the wavelength. Blue light has less wavelength than red light. Therefore, it becomes narrower and crowded together

28.

An element of group of 14 has two common allotrop a andb.A is very hard and is bad conductor of electricity while b is soft to touch and good conductor of electricity.Identify the elements and its allotropes. Explain reasons for their different properties.

Answer»

HEY MATE!


ELEMENT-CARBON


ALLPTROPE A-DIAMOND


ALLOTROPE B-GRAPHITE


THE REASON FOR THE DIFFERENT PROPERTIES IS DUE TO STRUCTURAL AND MOLECULAR DIFFERENCE BETWEEN THEM.


I HOPE IT HELPS YOU!



29.

What is metaphysics? Explain the basic principles of metaphysics?

Answer»

Metaphysics is a major branch of philosophy. It ISSUES existence and therefore the nature of things that exist. Altogether it's a theory of reality. metaphysics is that the a part of philosophy that discusses what exists: the classes of being. philosophy is that branch of philosophy that studies queries of being, becoming, existence, reality and therefore the nature of 'entities', 'objects' and different 'things'. The word "metaphysics" comes from 2 Greek words that, together, virtually mean "after physics". Areas of metaphysical studies EMBODY metaphysics, cosmology, and often, philosophy. Metaphysical - Longer definition: philosophy could be a form of philosophy or study that uses broad ideas to assist outline reality and our understanding of it.

Outline of a metaphysical conception of CONTEMPORARY science is conferred during which a BASIC distinction is drawn between scientific principles, laws and theories. On this read, metaphysics principles, instead of e.g. empirical knowledge, represent the core of science. the foremost basic of those principles area unit 3 in variety, being, a lot of significantly

(A) The principle of the uniformity of nature,

(B) The principle of the permanence of substance, and

(C) The principle of relation.

These 3 principles set basic constraints on the methodology of each empirical and theoretical science. The uniformity principle is central to the empirical side of science, suggesting a technique consisting within the decide to discover empirical laws, whereas the relation principle is central to the theoretical side of science, suggesting the postulation of scientific theories capable of indicating the causative basis of the laws. and therefore the permanence principle functions thus on type a bridge between the theories and therefore the laws. By distinctive between principles, laws and theories during this means, a dimension is interplanetary to the analysis of contemporary science that permits for a a lot of realistic account of its nature.

30.

A 400kg satellite is in a circular orbit of radius 2R about the earth.Calculate the energy needed to transfer it to a circular orbit of radius 4R.Find the changes in its kinetic energy and its kinetic energy and its potential energy .(Given R=6400 km radius of earth; g = 10 m/s2).

Answer» SEE the PIC I SEND it
31.

In which medium a ray of light incident obliquely at same angle would bend?

Answer» REFLECTED RAY =INCIDENT ray
32.

fish underwater a fish underwater is viewing obliquely a fisherman standing on the bank of Lake does the man look taller or shorter

Answer» SHORTER in STILL WATER and TALLER in NON still water
33.

A geostationary satellite orbits around the earth in a circular orbit of radius 36000 km then speed of spy satellite orbiting if you 100 km above the earth's surface will approximately be

Answer» THANKS for the QUESTION of
34.

Method of refraction of light using laser and soap water

Answer»

Refraction of light is the phenomena by which a single mono chromatic source of light IMAGE AREA which is deviated by another medium BUILD it PASSES through it this is easily seen when will look through the one side of a glass at a pencil on the other side


to do an experiment to observe refraction we use a laser and soap SOLUTION replace the breaker containing soap solution honest and with a white background behind a2b than sign the laser lights directly at the soap solution and observe it from the side against the white background


we will be able to observe the refraction of light to when we look at the given set up however play question must be taken that one does not directly look into the laser as it will damage the eye and its sensory Nerve cells

35.

Force acting on two bodies is proportional to product of what?

Answer»

Newton 's law UNIVERSAL gravitation STATES that every. Lost in the universe ATTRACT every other point mass with the force that is directly PROPORTIONAL to the product of their masses and INVERSELY proportional to the square of the distance between them

36.

What are highway materials? Explain.

Answer»

I road SURFACE or pavement is that DURABLE surface MATERIAL let down on an area INTENDED to sustain vehicular or foot TRAFFIC such as a road or walkway

37.

What are the uses of map study in engineering surveys for highway location?

Answer»

The most IMPORTANT purpose of the political MAP is to show territorial borders :the purpose of the physical is the show features of GEOGRAPHY such as mountain SOIL type or land use including infrastructure such as Road, rail road and BUILDING

38.

Show that Newton's second law of motion is real law of motion.

Answer»

Other LAWS of NEWTON can be derived from Newton's second law. Hence it is called REAL law of Newton

For eg…

2nd law is…F=ma

And 1ST law is …initial velocity=final velocity

Assume that force acting on body is zero

F=ma

so…0= ma

0/m = a

0=a

0= (v-u)/t

0/t = v-u

0= v-u

U=v

Thus ….we PROVED that 1st law can be derived from 2nd law of Newton

39.

Using the mirror formula obtain relation between m and f

Answer» MAGNIFICATION, m = – V/u


Mirror formula is 1/F = 1/v + 1/u


or, 1/v = 1/f – 1/u


or, v = uf / (u -f)


THEREFORE, m = v/u = f / u -f  

40.

For the body moving along a straight line with uniform acceleration, write the equation of motion.

Answer» V = U + at.

Where, V = FINAL velocity

U = INITIAL velocity

A = acceleration

T = Time.

Thanks...
41.

What is the duration of persistence of vision??

Answer»

The DURATION of PERSISTENCE of vision is 1/30 TH part of a SECOND

42.

What is radiant heat?

Answer»

Hello mate

Here is your answer,

Heat does not rise. Heat goes to cold. Hot AIR rises.This type of heat is called radiant heat, which is the process in which energy is emitted, as PARTICLES or waves, by one BODY and transmitted through an intervening medium or space, then ABSORBED by another body.

43.

Discuss Focus and Epicentre

Answer»

The PART of YHE MIRROR is FOCUS.....

44.

What is ichthyophobia?

Answer»

HIII

ICHTHYOPHOBIA :-------

IT IS THE FEAR FROM TOUCHING,EATING FISH.


HOPE THIS HELPS YOU
PLEASE MARK AS BRAINLIEST

45.

The wavelength of the matter wave is independent of - mass , velocity , momentum , charge

Answer»

The WAVELENGTH of the MATTER WAVE is INDEPENDENT of (C) momentum.

Thanks...!

46.

Does each incident photon essential to eject a photoelectron

Answer»

No it is not NECESSARY. because ENERGY of some PHOTONS are LOW that they cannot eject electron

47.

a particle executes shm with an amplitude of 10cm and time period 6s.At t=0 it is at position x=5cm going towards positive x-direction .Write the equation for the displacement x at time t.Find the magnitude of the acceleration of the particle at t=4s.

Answer» AMPLITUDE , A = 10cm
time period, T = 6 SEC
we know, angular frequency , \omega = 2π/T = 2π/6 = π/3 rad/sec.

equation of SHM, <klux>X</klux>=Asin(\omega t+\Phi)
at t = 0, x = 5

so, 5 = 10sin(π/3 × 0 + \Phi)
1/2 = sin\Phi
\Phi = π/6

HENCE, equation of SHM, x = 10sin(π/3 t + π/6)

we know, acceleration , a=-\omega^2x
at t = 4sec ,
x = 10sin(π/3 × 4 + π/6)
= 10sin(4π/3 + π/6)
= 10sin(9π/6)
= 10sin(3π/2)
= -10cm = -0.1 m

so, acceleration , a = -(π/3)² × (-0.1) = π²/9 m/s²


48.

A piece of mass 40g is added to 200g of water at 50°c.calculate the final temperature of water when all the ice has melted.specific heat capacity ofwater=4200J/kg/K and specific latent heat of fusion of ice=336×10³J/kg.

Answer»

⛦Hᴇʀᴇ Is Yoᴜʀ Aɴsᴡᴇʀ⚑
▬▬▬▬▬▬▬▬▬▬▬▬☟

Let t be the final TEMPERATURE.

➧ Then HEAT Liberated by water
➾ m X c x Δt           

➾ [200 x 10-3  x 4.2 x 103 x (50 – t)]

➾ (42,000 – 840t) 


➧ Heat absorbed by ice to change into water at 0oC
➾ 40 x 10 x 336 x 103 
➾ 13,440 J.


➧ Heat absorbed by water to change its temperature from 0oC to toC
➾ (40 x 10-3 x 4.2x 103 x t)
➾ 168t

➧ Total heat absorbed by water
➾ (13,440 + 168t) J

➧ According to the principle of calorimetry,

➧ Heat given = Heat taken

42000 – 840t
➾ 13440 + 168t

♦ 42000 – 13440
➾ 168t + 840t

♦ 1008t = 28560

t = 28560 / 1008
➾ 28.33oC ...✔

__________
Thanks...✊

49.

Why is it easier to swim in sea water than in river water.

Answer»

Because it CONTAINS more DISSOLVED SALT

50.

A cell converts into what ?

Answer» CELL CONVERTS into tissue if SIMILAR CELLS are attracted by ech other