InterviewSolution
Saved Bookmarks
InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 651. |
Formula stating relation between focal length of a lens, object distance and image distance |
| Answer» SOLUTION :LENS FORMULA | |
| 652. |
Fleming's left-hand rule is called as the motor rule and Fleming's right-hand rule is known as the generator rule. |
|
Answer» |
|
| 653. |
A person travels along a straight road for the first half length with a velocity v_(1)and the second half length with velocityv_(2). What is the mean velocity of the person ? |
|
Answer» `(2)/(V)=(1)/(v_(1))+(1)/(v_(2))` `V= (S_(1)+S_(2))/(t) = ((V_(1)t)/(2)+(V_(2)t)/(2))/(t)` `V_(1)=(S_(1))/(t//2), V_(2)=(S_(2))/(t//2)` `=(V_(1)+V_(2))/(2)` |
|
| 654. |
On what factors does the direction of force experienced by a conductor when placed in a magnetic field depend ? |
| Answer» SOLUTION :The direction of FORCE depends on the direction of CURRENT and direction of MAGNETIC field. | |
| 655. |
What potential difference is needed to send a current of 5A through the electrical appliance having a resistance of 18 Omega? |
| Answer» SOLUTION :POTENTIAL DIFFERENCE`V=RI=18 TIMES 5=90V` | |
| 656. |
Explain Right hand thumb rule. |
Answer» Solution :Fleming.s right hand thumb rule. Stretch the forefinger, CENTRAL finger and thumb of right hand in  mutually perpendicular DIRECTION. If the forefinger points in the direction of magnetic field, thumb points along the direction of MOTION of the conductor, then the central finger points in the direction of INDUCED current. |
|
| 657. |
In what way the leech is used in ayurvedic system of treatment ? |
| Answer» Solution :LEECHES are blood SUCKING ectoparasite . In Ayurvedic LEECH is usedto remove impure blood and blood clots. Such blood is sucked up by leeches and then the patient gets some relief . In the leech body there is a substance called hirudine which prevent blood clotting as it sucks up the blood . This hirudine is also used for MEDICINAL purpose. | |
| 658. |
In refraction of light, what does Snell's law state ? |
| Answer» SOLUTION :The RATIO of sine of ANGLE of INCIDENCE to the sine of angle of refraction remain constant subject to CERTAIN conditions. This is called refraction. | |
| 659. |
A positively-charged particle (alpha-particle) projected towards west is deflected towards north by a magnetic field. The direction of magnetic field is : |
|
Answer» towards south. |
|
| 660. |
A person standing on a rotating disc stretches out his hands, the angular speed will |
|
Answer» Increase L=1w = constant, So W decreases. |
|
| 661. |
What is the cause of dispersion of white light on passing through a prism? |
| Answer» SOLUTION :The REFRACTIVE index of the materials of a prism is different for different colours of light as different SPEED in the material of a prism, Also, prism has non- parallel SURFACES. | |
| 662. |
Name the screen on which an image is formed in the eye. What is the range of vision of a normal human eye ? |
| Answer» Solution :IMAGE is formed on the retina of the eye. The range of VISION of a normal HUMAN eye is from 25 CM to INFINITY. | |
| 663. |
Nametwo safety measure commonly used in electric circuitsand appliances . |
|
Answer» SOLUTION :(1) A safety fuseof PROPER RATING: Itprevents damgeto theappliancesand circuitdve to OVERLOADING . (2)An earthwire : It prevents possibleelectric shock whenthe livewireaccidentally touches themetalic body of an appliance . |
|
| 664. |
Complete the following flow chart as per the given instructions : |
|
Answer» Solution :GASTRIC secretions and their functions : a `rarr` HCL, d `rarr` Makes the medium acidic so that INACTIVE PEPSINOGEN is converted to active pepsin. b `rarr` Mucus, e `rarr` Protects stomach lining from action of acid. c `rarr` Pepsin, f `rarr` Acts on proteins and breaks them into DIPEPTIDES. |
|
| 665. |
An electric bulb is rated 220V and 100W. When it is operated on 110V the powerconsumed will be …………… . |
|
Answer» 100W So, the resistance of the FILAMENT of the bulb is `R = V^2/P` `=((220)^2)/100` `=484 OMEGA`  Now, the power consumed by the bulbwhen it is OPERATED at 110 V is given by `P. +(V.^2)/(R)` ` =((110)^2)/(484) = (110xx110)/484 =25 W` |
|
| 666. |
2g of lead nitrate powder is taken in a boiling tube. The boiling tube is heated over a flame. Now answer the following (a) State the colour of the fumes evolved and the residue left. (b) Name the type of chemical reaction that takes place stating its balanced chemical equation. |
|
Answer» Solution :(a) Brown coloured fumes of `NO_(2)` gas are EVOLVED , residue left is SOLID white LEAD oxide (B) It is a thermal decomposition reaction. `2PB(NO_(3))_(2) overset("Heat")to 2PbO+4NO_(2) uarr "(Brown fumes)" +O_(2) uarr` |
|
| 667. |
A tourch bulb is rated at 3 V and 600 mA. Calculate a) Power b) Resistance c) Energy consumed if it is used for 4 hour. |
|
Answer» Solution :`V=3V` and `I=600mA=600xx10^(-3)A` (a) Power = VI `=3xx600xx10^(-3)` `=1800xx10^(-3)` `=P=1.8` W (or watt. (b) Resistance (R )`=(V)/(I)` `=(3)/(600xx10^(-3))` `R=5Omega` (c ) Power (P) `=1.8" W and"` Time = 4 hours `=4xx60xx60=14400` second Energy consumed `E=Pxxt` `=1.8xx14400` `=25920` joules `E=25.9KJ` |
|
| 668. |
Two caricatures presenting the situations of the year 1998 and 2017 about playing on playground are given in the picture 9.5 in your textbook. Observe those caricatures. Express your opinion about arising of such different situations. |
|
Answer» Solution :In 1998, MOBILE phones, computers, internet services were not as common as they are now. DUE to this children used to spend more time oplaying outdoors. ii. The first picture of year 1998 shows a mother trying to stop her SON from playing outdoor and get him to study at home. iii. Whereas the second picture is of the year 2017, wherein the impact of mobile and computer games have increased. Due to this children spend a lot of time indoors and have little or no physical activity. This affects their social, mental and physical health. iv. The overuse of computers, internet, and mobilies in today,s generation not only affects physical health of children but also creates selfishness among them. v. In the second picuture, the mother is convincing her son to go out to play rather than sitting at home and WASTING time WATCHING television or on the internet, etc. |
|
| 669. |
Alkane and Alkene . |
Answer» SOLUTION :
|
|
| 670. |
If K is the kinetic energy of a projectile fired at an angle 45°, then what is the kinetic energy at the highest point. |
|
Answer» `(K)/(4)` At highest pt., `NU = v cos45^(@)` ` K.E =(1)/(2) m((v)/(SQRT(2)))^(2)=(v)/(sqrt(2))` `=(1)/(2) (mv^(2))/(2)=(K)/(2)` |
|
| 671. |
Mention the colour convention for live, neutral and earth wires. |
| Answer» Solution :Live WIRE - RED, Neutral Wire - BLACK, Earth wire- Green. | |
| 672. |
Why are Thermal Power Stations usually located near a river ? |
|
Answer» |
|
| 673. |
Track the changes in methods of animal classification. How did the niethods of animal classification change over time? |
|
Answer» SOLUTION :There were different methods of CLASSIFICATION of animals. (1) The first classification method was given by the Greek philosopher Aristotle. He took into ACCOUNT the criteria like body size, habits and HABITATS of the animals. This method was called artificial method of classification. (2) The same artificial method was used by other scientists such as Theophrastus, Pliny, John Ray, Linnaeus, etc. (3) Further due to advances in science the REFERENCES were changed and there were some new methods of classification proposed. ( 4) The system of classification called 'Natural system of classification' was then proposed. This system of classific_ation was based on criteria such as body organization, types of cells, chromosomes, bio-chemical properties, etc. (5) Later, Dobzhansky and Meyer gave the system of classification based on evolution. (6) In 1977, Carl Woese has also proposed the three domain system of animal classification. |
|
| 674. |
On the basis of the issues raised in this chapter , what changes would you incorporate in your lifestyle in a move towards a sustainable use of our resoures ? |
| Answer» Solution :I WOULD incorporate the MAXIMUM of the three R.s,I,e., reduce , recycle and reuse in my life - style in amove TOWARDS SUSTAINABLE use of our resources. | |
| 675. |
When the angle of incidence is 90, what is the angle of refraction. |
| Answer» SOLUTION :The angle of refraction is ZERO (0) degree. | |
| 676. |
District disaster management authority: Collector:: Village level Committee Chairman :______________ |
|
Answer» Solution :Sarpanch The COLLECTOR is the district DISASTER management AUTHORITY, whereas the sarpanch is the village level COMMITTEE CHAIRMAN. |
|
| 677. |
How much heat should be supplied to convert ice of mass 50 g at 0^@C into water at 40^@ C ? |
|
Answer» Change in temperature `(DELTA T)` `= 40-0-40 ^@C` We KNOW that: Latent heat of melting of ice `=L=("melt")=80 cal//g` ,Specific heat of water `C_("w")=1 cal//g^@C` To find, Heat supplied (Q) Formulae: i Heat required to CONVENT ice at `0^@C` into water at `0^@C " is " Q_1=mL_("melt")` ii. Heat required to raise temperature of water from `0^@C`to `40^@C` is `Q_2= mxxC_w xx Delta T` Calculation: From formula (i), `Q_1=50 xx 1 xx (40-0)=2000` cal TOTAL heat energy required `Q=Q_1+Q_2` `=4000 +2000=6000 cal` |
|
| 678. |
________ is basedon the law of conservation of linear momentum . |
| Answer» SOLUTION :PROPULSION of ROCKETS | |
| 679. |
A train 50m long passes over a bridge at a velocity of 30 km/m. If it takes 36 s to cross the bridge, the length of the bridge will be |
|
Answer» 100 m `:. (50+l)/(36)=30xx(1000)/(3600)` or""50+l=300 or"" l=250m |
|
| 680. |
if crushed ice is pressed and then the pressure is released, a lump of ice is formed. |
| Answer» SOLUTION :(1) When crushed ice is PRESSED, its melting point is lowered and some ice MELTS to form water. (2) When PRESSURE is released, the melting point becomes normal and the water freezes to form ice forming a LUMP. | |
| 681. |
The princple of working of a motor is |
|
Answer» there is a magnetic FIELD around a CURRENT carrying conductor |
|
| 682. |
Unit of electric power may also be expressed as |
|
Answer» VOLT ampere |
|
| 683. |
A current is passed through a straight wire. The magnetic field established around it has its lines of forces |
|
Answer» circular |
|
| 684. |
Which of the following is needed for the formation of biogas from cow-dung and which is not ?Water,Oxygen |
|
Answer» |
|
| 685. |
At high temperature, the molecules of a substance |
|
Answer» MOVE more vigorously |
|
| 686. |
A gas behaves as an ideal gas at |
|
Answer» LOW PRESSURE and HIGH temperature |
|
| 687. |
Which are the objectives of disaster management? |
|
Answer» Solution :State any four objectives of disaster management. (1) To save human life from disasters. To help them for moving AWAY from the place of disasters by rapid action. (2) To supply essential commodities to the affected people. This helps to REDUCE the gravity of disaster. People are given grains, WATER and clothes and other basic necessities under this objective. (3) To bring back the conditions of affected people to NORMALCY. (4) To rehabilitate the affected and displaced victims. (5) To think and execute the protective MEASURES in order to develop capability to face the disasters in future. |
|
| 688. |
The sum of the numbers 436.32, 227.2 and 0.301 in appropriate significant figures is |
|
Answer» 663.821 |
|
| 689. |
(a) Write the special name given to the coil AB which has many circular turns of insulated copper wire. (b) List two factors on which the strength of the magnetic field produced by AB depends. (c) What is the effect of placing an iron core in the coil AB? |
|
Answer» SOLUTION :(a) Coil AB is a SOLENOID. (b) (i) Strength of the current. (ii) Number of turns in the coil. (c) The magnetic FIELD associated with the solenoid INCREASES tremendously. It BECOMES an electromagnet. |
|
| 690. |
Draw the diagram of a simple electric motor. Label the following parts. i) Split rings ""ii) Brushes |
Answer» SOLUTION :
|
|
| 691. |
When n resistors of equal resistance (R ) are connected in series, the effective resistance is …………… . |
|
Answer» `NR` |
|
| 692. |
(i) A torch bulb is rated at 3V and 600 ma . Calculate it's (a) power (b) resistance (c) energy consumed if it used for 4 hours. (ii) Why does sound travel faster on a rainy day than on a dry day ? |
|
Answer» Solution :Given V = 3 V I = 600 mA = `600 xx10^(-3) A` (a) Power (P) = VI = `3xx 600 xx10^(-3) = 1800xx10^(-3)` = P = 1.8 W (or) watt. (b) RESISTANCE `(R) =V/I` `R = (3)/(600xx10^(-3) ) =(3xx10^3)/(600)=3000/600` (C) Power P = 1.8 W and t = 4 hours `4 xx60xx60=14400`second Energy CONSUMED `(E) = P xxt ` ` = 1.8xx14400=25920` joules E = 25. WH (ii) When humidity increase the speed of sound increase . That is why we can hear sound from long distance clearly during rainy season. |
|
| 693. |
The degree of hotness or coldness of a body is called__________. |
|
Answer» Energy |
|
| 694. |
Under which of the following conditions a concave mirror can form a real and inverted image larger than the actual object ? |
|
Answer» When object is kept at CENTRE of curvature of the mirror. |
|
| 695. |
According to Joule's law the amount of heat produced in a given resistor in a given time is directly proportional to the current I flowing through it. |
| Answer» Solution :FALSE- As per JOULE law amount of heat produced in a CONDUCTOR is GIVEN as `H=I^2RT i.e. H PROP I^2` | |
| 696. |
The energy of an electron is 4.0 xx10^(-19) J.Express it in eV. |
|
Answer» SOLUTION :SINCE 1 eV=`1.6xx10^(-19)J` `THEREFORE 4.0 xx10^(-19)J=(4.0xx10^(-19))/(1.6xx10^(-19))eV=2.5eV` |
|
| 697. |
Let the period of revolution of a planet at a distance R from a star be T. Prove that if it was at a distance of 2R from the star, its period of revolation will be sqrt8T. |
|
Answer» Solution :`T= (2PI)/(SQRT(GM)) r^(3//2), ` where T = period of revolution of a planet around the sun, M= mass of the sun, G = GRAVITATIONAL constant and r = radius of the orbit assumed to be circular = distance of the planet from the sun. For` r= R and T = T_(1)` ` T_(1) = (2pi)/(sqrt(GM)) R^(3//2)` From r = 2 R and T = `T_(2)` ` T_(2) = (2pi)/(sqrt(GM)) (2R)^(3//2) = (2pi)/(sqrt(GM)) R^(3//2) xx 2^(3//2)= T_(1) xx 2^(3//2)` ` T_(2) = T_(1) sqrt(8) = sqrt(8)T` |
|
| 698. |
Choose the correct alternaive Which of the following satellite Iaunchers is developed by Indian ? |
|
Answer» INSAT |
|
| 699. |
Biogas is produced by the process of |
|
Answer» ANAEROBIC FERMENTATION |
|