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.
| 4101. |
given\vec{p}=\vec{z}+a \vec{j}+\vec{k}\vec{q}=\vec{3 i}-\vec{j}-\vec{k}are perpendicular calculate the value of c |
|
Answer» perpendicular soP●Q=6-a-1=05-a=0so a=5 if there are at 60 degrees what result |
|
| 4102. |
äşş fanallelalale , condenser |
|
Answer» Lorentz force - qvbsin(theta)potential energy due to electric dipole - -PEcos(theta)quantization of charge - Q=neInternal Resistance- R(E/V -1)parallel plate condenser- EA/d |
|
| 4103. |
A radioactive substancehasahalflifeof30days.Calculatethe time taken for 1/8 of all the originalnumber of atoms to remain unchanged. |
| Answer» | |
| 4104. |
58. At some instant two radioactive substance arehaving amount in ratio of 2:1. Their half lives are12 hrs and 16 hrs then after two days the ratio oftheir quantities is |
|
Answer» 2:1 m reason koni debate.......... ........... We will take hours as units for time t and decays per hour (3600 Bq) as unit for decay constant for the solution below. (instead of per second). Here, when we say an amount of substance, it means the number of Nuclei or atoms. The amounts of the two substance will become equal. That is both substances will have same number of (atoms or) Nuclei. |
|
| 4105. |
is used for making household utensils. J |
|
Answer» Pots, pans, and other toolsusedincookingoften do more than just hold the food. ... Common materialsusedincookwareandutensilsare: Aluminum. Copper. |
|
| 4106. |
Derive the relation between half life and mean life |
| Answer» | |
| 4107. |
6. The mean life of a radioisotope is 15 hours. Its[2012 (A)half-life in hours will be(ii) 10.4(iv) 30(ii) 21.1 |
| Answer» | |
| 4108. |
Draw theWhat do you find the major difference in these apparatus?figures of arrangement of apparatus for distillation and fractional distillation. |
|
Answer» Definition of distillation: the action of purifying a liquid by a process of heating and cooling. (noun) Fractional distillation is the separation of a mixture into its component parts, or fractions, separating chemical compounds by their boiling point by heating them to a temperature at which one or more fractions of the compound will vaporize. most mixture can be separated and the kind of separation methods here are some common method for separating mixture of two solid with one part of having magnetic properties |
|
| 4109. |
A body of mass m starts moving from restalong x-axis so that its velocity varies as3.avs where a is a constant and s isthe distance covered by the body. The totalwork done by all the forces acting on thebody in the first t seconds after the start ofthe motion is:matt(2) 8 m a t2(3) 4 m 4 t24 |
| Answer» | |
| 4110. |
Throan activit ghoul thegresenaeaatmos pheric pressou. |
|
Answer» you can perform atmospheric pressure existence activity bytaking a glass.and wrape a tissue and keep it in the glass.now take a big bowl full of water and keep the glass tilted in bowl.that is facing upside down you can find that the tissue in the glass doesn't get wet..... so by this experiment you can prove the presence of atmospheric pressure around you....... |
|
| 4111. |
A light of wavelength 6000 A in air, enters a mediumof refractive index 1.5. What will be the frequencyand wavelength of light in the medium? |
| Answer» | |
| 4112. |
prolt33 UAray of light enters a diamond from air. If therefractive index ofdiamond is 2.42, what % (percent)isspeed of light in diamond with that of speed in air? |
| Answer» | |
| 4113. |
Example 14. A light of wavelength 6000 A in air, enters amedium with refractive index 1.5. What will be the frequencyand wavelength of light in that medium ?IIT 971 |
|
Answer» c = Speed of light in air → 3 X 10^8 m/s W → Wavelength n → Refractive index of the medium = 1.5 W in air = 6000 A = 6 X 10^-7 metres λ → Frequency in air = c / W in air = 5 X 10^14 Hz n = W in air / W in the medium 1.5 = 6000 / W in the medium W in the medium =4000 A Magnitude of frequency depends upon the light producing source hence it remains constant throughout (5 X 10^14 Hz) . |
|
| 4114. |
2. Why can we not see stars during the day? |
| Answer» | |
| 4115. |
A light of wavelength 6000 Aof refractive index 1.5. What will be the frequeand wavelength of light in the medium?in air, enters a mediumncy(Ans: 5 x 10 Hz, 4000 A) |
|
Answer» When light enters an optically denser medium, it’s velocity reduces while its frequency remains unchanged. Refractive index of a substance wrt vacuum can be equivalently defined as: Considering air to be equivalent to vacuum Refractive index of a medium wrt vacuum, n, = λ(in vacuum)/λ(in medium) or equivalently n = v(in vacuum)/v(in medium) =>λ(in medium) = λ(in vacuum)/1.5 = 6000/1.5 = 4000 Frequency (ν) does not change with medium. We know the wavelength and speed in air (or vacuum). So, ν = v(velocity in vacuum)/λ(wavelength in vacuum) =c/6000Å = 3*10^8/6*10^-7 = 5*10^14 Thank u so much |
|
| 4116. |
Light enters from air into diamond which has a refractive index of 242. Caculate the speed of light in diamondThe speed of light in air is 3-0 10 mCB.S.E. (All India) 2005 2011/ (Ans. 1.24 10m |
| Answer» | |
| 4117. |
how can you help reduce air pollution at the individual level? |
|
Answer» hi Here are some simple steps you can take: Avoid smoking indoors (quitting smoking is the best answer for overall health)Use craft supplies in well-ventilated areas.Make sure your gas stove is well-ventilated.Minimize clutter.Remove carpeting if possible.Use a dehumidifier and/or air conditioner to reduce moisture. |
|
| 4118. |
18. Calculate the energy radiated per minute from thefilament of an incandascent lamp at 2000K if thesurface area is 5 105 m and its relativeemittance is 0.85, Ď -5.7 10-8 MKS units: |
| Answer» | |
| 4119. |
11. Mention two ways by which the strength of a given electromagnet can be increased.2 |
| Answer» | |
| 4120. |
15. The effective resistance between points A and B of thenetwork shown in figure(A) 2 Ω(B) 3 Ω35(C) 6 Ω(D) 12 ΩCurrent Electricity131 |
|
Answer» the correct answer is (A) 2ohm |
|
| 4121. |
Calculate mass % of Carbon , Hydrogen , & Oxygen in Ethanol [ C2H5OH]Calculate mass % of oxygen and Hydrogen in water. |
| Answer» | |
| 4122. |
\left. \begin{array} { l } { ( 1 ) 215 ^ { \circ } F } \\ { ( 3 ) 329 ^ { \circ } F } \end{array} \right. |
|
Answer» The rate of degrees m = F/C = 180/100 = 1.8 deg F/deg C between freezing and boiling. So from the straight line general equation we can write F = m C + b = 1.8 C + 32, where F = 32 = b deg F when C = 0 deg C, the two freezing points. And there, we've just derived the equation for finding F from C. Using the physics. As it should be learned. Now you just plug and chug the derived equation. When C = - 183 deg, we have F = 1.8*(-183) + 32 = -297.4 deg F |
|
| 4123. |
If charge on left plane of the 5μ-capacitor in the circuit segment shown inthe figure is-201C, the charge on the right plate of 3μ-capacitor is |
|
Answer» The charge on 5 microfarad capacitor will be distributed in 3 and 4 microfarad capacitors in the ratio of 3:4 So, charge on 3 microfarad capacitor = 20/7 x 3 = 60/7 microfarad .. At right plate it will be -60/7 microfarad its +ve 60/7 |
|
| 4124. |
What would happen if weeds are not removed from the field ?Turn Over |
|
Answer» Weeding is the process to remove out the weeds. Weeds are unwantedvplants which grown along the useful crops. Weeding is required because weeds are competitive plants as they reduce the useful crop yield by acquiring space, fertilizers and nutrients from the soil. Weeds means unwanted plants for remove of these plant we use weediside (2,4 D) .If they are there in the field they take all nutrients of plant and plant can't grow properly. |
|
| 4125. |
37町驭41召[TTT: 71.1れ/Ho] |
| Answer» | |
| 4126. |
(1)Calculate the angular velocity andvelocity of a tip of minute hand of length 10cm. |
|
Answer» Solution:-Given –Radius of tip of minute hand = r=1 0 cm= 0.1 m. As minute hand takes one hour to complete one rotation (i.e. 360°or 2πradian); The time period of the tip of minute hand can be given as=T =1hr = 60 min = 3600 sec. The angular velocity of any particle performing circular motion can be given as time rate of change of angular displacement,W = (dθ)/ (dt) W= (2π) / TW= (2 X 3.14) / 3600W= 1.745 X 10-3rad / sec The linear velocity (v) at the tip of minute hand is V = r X wV = 0.1X 1.745 X 10-3V = 1.745 X 10-4m/s |
|
| 4127. |
3) 72 km/hr4) 144 km/hr16. If the particle is moving along a straight linegiven by the relation s 2 - 3t +4t where s isin ems., and t in sec. its average velocityduring the third sec is1) 73 cm/s2) 80 cm/s |
|
Answer» but answer is not there in options |
|
| 4128. |
What is the average speed of(a) a car which travels 400 m in 20 s,(b) an athlete who runs 1500 m in 4 minutes. |
| Answer» | |
| 4129. |
A concave mirror gives an image threethe image to be real, the focal length should betimes as large as the object placed at a distance of 20 cm from it. Foras the obj |
| Answer» | |
| 4130. |
3. A concave mirror produces a real image of size 3 times that of the object at a distance of 30 cmpole of the mirror. Find the position of the object.the(Sinilar C.RSE 20 |
|
Answer» Given: Object distance =u=-30cm(by sign convention)v=?height of object be =h cmheight of image=- 3h cm(real image)h=-v/u m=height of image/height of object⇒-3h/h = -v/uh3=v/u⇒v=uX3∵u=-30cmwe get v=-30x3⇒-90cmNegative sign indicates that image formed is real and inverted at a distance of 90cm from mirror. |
|
| 4131. |
A convex lens of focal lenghth f produces a real image x times the size of an object then the distance of the object from lens is?? |
|
Answer» please check the question as there seems to be some anomalies. no problems in question |
|
| 4132. |
20/ Ten positively charged particles are kept fixed on thecaxis at points x=10 cm, 20 cm, 30 cm, , 100 cThe first particle has a charge 1.0×10-8 C, the second8× 10-8 C, the third 27× 10-8 C and so on. The tenthparticle has a charge 1000 × 10-8 C. Find the magnitudeof the electric force acting on a 1 C charge placed at theorigin. kixi noutilos having charge 2.0x 10ch |
| Answer» | |
| 4133. |
A small sphere with a positive charge 1.7x 10 °C is touched to identical sphere with negatcharge 3x10-*C. Find the net force between them when they are 20cm apart |
|
Answer» Thank u |
|
| 4134. |
MPLE 1Charge 5.0 x 10-C, -2.5 x 10-7C and 1.0 x 10-7Care fixed at the corners A, B and C of an equilateraltriangle of side 5.0 cm. Find the electric force onthe charge at C due to the rest two. |
| Answer» | |
| 4135. |
celculatethe magnihude o the resultenhs? too veetors each of magnitude Sunitndlined to each ather at 30nein |
| Answer» | |
| 4136. |
B. The resistivity of a metal wire is 10 x 10-8 Ί m at 20°C. Find the resistance of thesame wire of 2 meter length and 0.3 mm thickness. |
| Answer» | |
| 4137. |
B. A concave mirror produces a real image of size 3 times that of the object at a distance of 30 cm from theSimilar C.B.S.E. 2011,)pole of the mirror. Find the position of the object. |
| Answer» | |
| 4138. |
1. What do you mean by D.C.power Supply? |
|
Answer» The termDCis used to refer topower systems that use only one polarity of voltage or current, and to refer to the constant, zero-frequency, or slowly varying local mean value of a voltage or current. For example, the voltage across aDCvoltagesourceis constant as is the current through aDCcurrent source. |
|
| 4139. |
11. A copper wire of radius 0'1 mm and resistance 1 kQ isconnected across a power supply of 20 V. (a) How manyelectrons are transferred per second between the supplyand the wire at one end ? (b) Write down the currentdensity in the wire. |
| Answer» | |
| 4140. |
VOT4. A copper wire of radius 0.1 mm and resistance 1k 52 is connected across a power supplyof 20 volt. How many electrons are transferred per second between the supply & thewire at one end?hem hemmeter A in the cit shown in fir |
| Answer» | |
| 4141. |
wton's Laws of MotionThree masses of 1 kg, 6 kg and 3 kg are connected to each other withiathreads and are placed on table as shown in figure. What is theacceleration with which the system is moving ? Take g 10m s(3) 2 m(1) Zero 2kg(2) 1 m s2(4)3 m s23kg |
| Answer» | |
| 4142. |
3. A concave mirror produces a real image of size 3 times that of the object at a distance of 30 cm fronSimilar C.B.S.E 2pole of the mirror. Find the position of the object. |
|
Answer» Given: Object distance =u=-30cm(by sign convention)v=?height of object be =h cmheight of image=- 3h cm(real image)h=-v/u m=height of image/height of object⇒-3h/h = -v/uh3=v/u⇒v=uX3∵u=-30cmwe get v=-30x3⇒-90cmNegative sign indicates that image formed is real and inverted at a distance of 90cm from mirror. |
|
| 4143. |
the focal length of a convex mirror whoseFind32 cm.radius of curvature is |
| Answer» | |
| 4144. |
d the focal lensth of a cones mirrr whose radius of eurof curvature i32 cm |
|
Answer» f=r/2 = -32cm/2=-16cm |
|
| 4145. |
(A) fRON(C) 3777 |
|
Answer» पदार्थ की प्रकृति चुंबकीय क्षेत्र पर निर्भर करती है |
|
| 4146. |
Two bodies of 6 kg and 4 kg masses have theirvelocity 5i-2)+10k and 10i-2/t5k resp-ectively. Then the velocity of their centre of massIS1) 51+2j -8k2) 71+2j-8k3) 77-2j+84) si-2j +8k |
|
Answer» Vcm = V1m1+v2m2/(m1+m2) Vcm = [(5i-2j+10i)*6+(10i-2j+5k)*4]/(6+4)Vcm = [(30+40)i+(-20j)+(80k)]/10Vcm = 7i-2j+8k option 3 |
|
| 4147. |
A football is kicked 20 m/s at a projection angle of 450. A receiver on the goal line 25 maway in the direction of the kick runs thesame instant to meet the ball. What must be his speed if he is to catch the ball before it hits the ground? |
| Answer» | |
| 4148. |
31.Two stones having different masses mi and m2 areprojected at angles θ and (90° -0) with samevelocity from the same point. The ratio of theirmaximum heights is(2) 1 : tan θ(4) tan'e 1(3)tan θ :1 |
|
Answer» hence ratio is tan^2theta:1 |
|
| 4149. |
53. Two blocks A and B of masses 5 kg and 3 kgrespectively rest on a smooth horizontal surfacewith B over A. The coefficient of friction between Aand B is 0.5. The maximum horizontal force(in kg wt.) that can be applied to A, so that therewill be motion of A and B without relative slipping, is2(2) 2.5(3) 4(4) 5 |
| Answer» | |
| 4150. |
Two blocks of masses 5 kgkick gives a velocity of 14 m/s to the heavier block in the direction of the lighter one. Calculate the velocitygained by the centre of mass.and 2 kg placed on a frictionless surface are connected by a spring. An externalVem m |
| Answer» | |