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. |
Two cars start off to race with velocities `4 m/s and 2 m/s` and travel in straight line with uniform accelerations `1 msec^-2`and 2 msec−2` respectively. If they reach the final point at the same instant, then the length of the path is.A. `30m`B. `32m`C. `20m`D. `24m` |
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Answer» Correct Answer - D Two cars ……………. `s=4t+(1)/(2)(1)t^(2)=2t+(1)/(2)t^(2)` `implies 4t+0.5t^(2)=2t+t^(2)` solving we get `t = 0 and t = 4 sec` so, `s = (4xx4)+0.5(4xx4)` , `s = 24m` |
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| 2. |
The time dependence of a physical quantity `P` is given by `P = P_(0)e^(-alpha t^(2))` , where `alpha` is a constant and `t` is time . Then constant `alpha` is//hasA. `[T^(-1)]`B. `[T^(-2)]`C. `[T^(1)]`D. `[T^(2)]` |
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Answer» Correct Answer - B `P = P_(0)e^(-alpha t^(2))` …………. `[alpha t^(2)]=[M^(@)L^(@)T^(@)]` `implies [alpha] = [T^(2)]` |
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| 3. |
Write the dimensions of `a//b` in the relation `P = ( a - t^(2))/( bx)` , where `P` is the pressure , `x` is the distance , and `t` is the time .A. `[M^(1)L^(0)T^(-2)]`B. `[M^(1)L^(2)T^(-2)]`C. `[M^(1)L^(1)T^(-1)]`D. `[M L^(1)T^(-2)]` |
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Answer» Correct Answer - A The dimension …………. `[P] = [(a)/(bx)] = [ct^(2))/(bx)]` `[M^(-1)L^(-1)T^(2)]= [(a)/(b)][(1)/(L)] implies [(a)/(b)] = [MT^(2)]` |
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| 4. |
A block of mass m is pulled by a constant powert `P` placed on a rough horizontal plane. The friction coefficient the block and surface is `mu`. The maximum velocity of the block is.A. `(p)/(mg)`B. `(mu p)/(mg)`C. `(p)/(mu mg)`D. `(p)/(N^(2)//mg)` |
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Answer» Correct Answer - C A block of …………… `FV = P` `v = (P)/(F)` foe max velocity `F` should be mminimum which is equal to `mu mg` just to drag the block `v_(max) = (P)/(mu mg)` |
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| 5. |
Assertion In isothermal process, whole of the heat energy supplied to the body is converted into internal energy. Reason According to the first laq of thermodynamics," "`triangleQ=triangleU+triangleW`A. Both Assertion and Reason are correct, Reason is the coreect expianation of AssertionB. Bioth Assertion and Reason are Correct but Reason is not the correct expalnation of AssertionC. Assetion is correct and Reason is incorrectD. Assertion is incorrect and Reason is correct |
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Answer» Correct Answer - A |
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| 6. |
Statement I: Smaller drops of liquid resist deforming forces better than the larger drops. Statement II: Excess pressure inside a drop is directly proportional to its surface area.A. Both Assertion and Reason are correct, Reason is the coreect expianation of AssertionB. Bioth Assertion and Reason are Correct but Reason is not the correct expalnation of AssertionC. Assetion is correct and Reason is incorrectD. Assertion is incorrect and Reason is correct |
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Answer» Correct Answer - D |
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| 7. |
if vectors xi + yj + zk = 2i + 3j - 5k ⇒ x + y + z =(A) 0(B) 5(C) 10(D) 9 |
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Answer» Correct option is: (A) 0 |
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| 8. |
Most famous centre of learning during the mauryan period |
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Answer» Most famous centre of learning during the mauryan period was Taxila |
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| 9. |
Which is the best thing |
| Answer» Everything is best if your perception is best. | |
| 10. |
Maxwell-Wien bridge is used for measuring (a) capacitance (b) dielectric loss (c) inductance (d) phase angle |
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Answer» (c) inductance |
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| 11. |
Hay’s bridge is particularly useful for measuring (a) inductive impedance with large phase angle (b) mutual inductance (c) self inductance (d) capacitance and dielectric loss |
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Answer» (a) inductive impedance with large phase angle |
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| 12. |
Maxwell’s L/C bridge is so called because (a) it employs L and C in two arms (b) ratio L/C remains constant (c) for balance, it uses two opposite impedances in opposite arms (d) balance is obtained when L = C |
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Answer» (c) for balance, it uses two opposite impedances in opposite arms |
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| 13. |
This binding energy per nucleon for the parent nucleus is `E_(1)` and that for the daughter nuclei is `E_(2)`. ThenA. `E_(1) = 2E_(2)`B. `E_(1)gtE_(2)`C. `E_(2)gtE_(1)`D. `E_(2)=2E_(1)` |
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Answer» Correct Answer - C Energy is released `:. (B.E)_("product") gt (B.E)_("Reactant")` |
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| 14. |
The binding energy per nucleon for the parent nucleus is E1 and that for the daughter nuclei is E2. Then(1) E2 = 2E1 (2) E1 > E2 (3) E2 > E1 (4) E1 = 2E2 |
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Answer» (3) E2 > E1 After decay, the daughter nuclei will be more stable hence binding energy per nucleon will be more than that of their parent nucleus. |
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| 15. |
A positive charge Q is uniformly distributed throughout the volume of a dielectric sphere of radius R. A point mass having charge +q and mass m is fired toward the center of the sphere with velocity v from a point at distance `r (r gt R)` from the center of the sphere. Find the minimum velocity v so that it can penetrate `(R//2)` distance of the sphere. Neglect any resistance other than electric interaction. Charge on the small mass remains constant throughout the motion. |
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Answer» Correct Answer - `sqrt((2KQq)/(mR)((r-R)/r+3/8))` From the energy conservation `(KQq)/r+1/2 mv(2)=11/8(KQq)/R+0` `v=sqrt((2KQq)/(mR)[11/8-R/r])` |
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| 16. |
A source of sound of frequency `1.8kHz` moves uniformly along a straight line at a distance `250m` from observer. The velocity of source is `0.8C` where `C` is the velocity of sound. Find out the frequency of sound received by observer (in kHz) at the moment when the source gets closest to him. |
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Answer» Correct Answer - 5 . |
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| 17. |
The middle term of arithmatic series 2, 6, 10, ...,1461. 702. 793. 744. 83 |
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Answer» Correct Answer - Option 3 : 74 Concept: Let us consider sequence a1, a2, a3 …. an is an A.P.
Calculation: Given series is 2, 6, 10, ...,146 First term, a = 2, last term, an = 146, an Common difference d = 4, so it is an AP an = a + (n – 1) d 146 = 2 + (n - 1) (4) ⇒ n - 1 = 144/4 ⇒ n = 36 + 1 = 37 So, number of terms in given series = 37 Middle term = (37 + 1)/2 = 19th term a19 = 2 + (19 - 1) × 4 = 2 + 72 = 74 Hence, option (3) is correct. |
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| 18. |
If the arithmetic mean of a, b, c is \(\rm \frac M 3\) and \(\rm \frac{1}{a} + \frac{1}{b} = -\frac{1}{c} \), then the arithmetic mean of a2, b2, c2 is1. M2/32. 3M23. 6M24. 9M2 |
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Answer» Correct Answer - Option 1 : M2/3 Concept: The arithmetic mean is the sum of all the numbers in a data set divided by the quantity of numbers in that set.
Calculation: Given: Arithmetic mean of a, b, c is \(\rm \frac M 3\) So, \(\rm \frac M 3 = \frac {a+b+c}{3}\) ⇒ M = a + b + c .... (1) Given: \(\rm \frac{1}{a} + \frac{1}{b} = -\frac{1}{c} \) ⇒ \(\rm \frac{1}{a} + \frac{1}{b} +\frac{1}{c} =0\) ⇒ \(\rm \frac {ab + bc+ac}{abc} = 0\) ⇒ ab + bc + ac = 0 .... (ii) As we know, (a + b + c)2 = a2 + b2 + c2 + 2(ab + bc + ac) ⇒ M2 = a2 + b2 + c2 + 2 × 0 [From equation (i) and (ii)] ∴ a2 + b2 + c2 = M2 Now, the arithmetic mean of a2, b2, c2 = \(\rm \frac {a^2+b^2+c^2} 3 = \frac {M^2}3\) |
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| 19. |
A point mass m and charge q is connected with massless spring of natural length L. Initially spring is in its natural length. If a horizontal uniform electric field E is switched on as shown in figure, then the maximum separation between the point mass and the wall is: (Assume all surface are frictionless) A. `L +(2qE)/(K)`B. `L+(qE)/(K)`C. LD. None of these |
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Answer» Correct Answer - A `(1)/(2)Kx^(2) = (qE)x` `x = (2qE)/(K)` `:. x_(max) = L +(2qE)/(K)` |
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| 20. |
`X` and `Y` are large, parallel conducting plates close to each other. Each face has an area `A`. `X` is given a charge `Q`. `Y` is without any charge. Points `A,B` and `C` are as shown in the figure. A. The field at B is `Q/(2epsilon_(0)A)`B. The field at B is `Q/(epsilon_(0)A)`C. The field at A, B and C are of the same magnitudeD. The field at a and C are of the same magnitude, but in opposite directions |
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Answer» Correct Answer - A::C::D Surface charge density at inner surface of X is `sigma=Q/(2A)` `:.` Electric field at B due to this is `sigma/(2 in_(0))=Q/(4pi in_(0))` Toward right and in same direction of same value due to induced charged precent inside surface of plate Y. |
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| 21. |
Two concentric conducting thin spherical shells A andB having radii rA and `r8 (r_(8) gt r_(A))` are charged to `Q_(A)` and `- Q_(B)(|Q_(B)| gt |Q_(A)|)`. The electric field strength along a line passing through the centre varies with the distance x as :A. B. C. D. |
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Answer» Correct Answer - C `{:(E_(A)=0,r lt r_(A)),(E_(A)=(KQ)/(r^(2)),r_(a)ltrlt r_(B)),(E_(B)=(KQ_(A))/(r^(2))-(KQ_(B))/(r^(2)),rgt r_(A)gt r_(B)):}` |
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| 22. |
In column-II liquid (s) are fillied in a container of large base area as shown in the figure. If h is the height above the ground where a small hole to be made in order to get maximum range,R. v is the velocity with which the liquid comes out from the hole and t is the time taken by the liquid to reach ground just aftr the hole is made. Then match the column I with column II |
| Answer» Correct Answer - `A(P,Q,R,S,T)B(P,Q,S,T)C(Q,R,S,T)D(P,Q,R,S,T)` | |
| 23. |
Statement I: The temperature coefficient of resistance is always positive.Statement II: The resistance of metal and its alloys increases with the rise of temperature. Of these statements :(a) Both the statements are true and Statement II is the correct explanation of Statement I. (b) Both the statements are true, but Statement II is not the correct explanation of Statement I. (c) Statement I is true, but Statement II is false.(d) Statement I is false, but Statement II is true. |
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Answer» (a) Both the statements are true and Statement II is the correct explanation of Statement I. |
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| 24. |
One end of a taut string of length 3m along the x axis is fixed at x = 0. The speed of the waves in the string is 100 ms-1 . The other end of the string is vibrating in the y direction so that stationary waves are set up in the string. The possible waveform(s) of these stationary waves is (are)(A) y(t) = A sin πx/6 cos 50πt/3(B) y(t) = A sin πx/3 cos 100πt/3(C) y(t) = A sin 5πx/6 cos 250πt/3(D) y(t) = A sin 5πx/2 cos 250πt |
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Answer» (A) y(t) = A sin πx/6 cos 50πt/3 (C) y(t) = A sin 5πx/6 cos 250πt/3 (D) y(t) = A sin 5πx/2 cos 250πt Taking y(t) = A f(x) g(t) & Applying the conditions: 1; here x = 3m is antinode & x = 0 is node 2; possible frequencies are odd multiple of fundamental frequency. where, Vfundamental = v/4l = 25/3 Hz |
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| 25. |
Two coils of self inductance L1 and L2 are connected in series combination having mutual inductance of the coils as M. The equivalent self inductance of the combination will be :(A) 1/L1 + 1/L2 + 1/M(B) L1 + L2 + M(C) L1 + L2 + 2M(D) L1 + L2 - 2M |
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Answer» Correct option is (D) L1 + L2 - 2M Current on both the inductor is in opposite direction. Hence: Leq = L1 + L2 - 2M |
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| 26. |
The figure below shows a graph of potential energy U(s) verses position x for a particle executing one dimensional motion along the x axis. The total mechanical energy of the system is indicated by the dashed line. At t=0 the particle is somewhere between points A and G. For later times choose the correct statement:- A. The magnitude of force is maximum at `D`B. The kinetic energy is maximum at `B`C. The velocity is zero at `A` & `G`D. The magnitude of force is minimum at `F` |
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Answer» Correct Answer - C `F=-(dU)/(dx)` and `K+U=E` |
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| 27. |
Which of the following statemente is `/` are INCORRECT? `(a)` Mechanical energy is the sum of kinetic energy and potential energy. `(b)` Potential energy is a relative quantity. It depends on the choice of reference point. `(c )` Kinetic energy must be non negative. `(d)` Potential energy must be postive.A. `(b)` onlyB. `(a)` and `(b)` onlyC. `(d)` onlyD. `(c )` and `(d)` only |
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Answer» Correct Answer - C Potential energy can be positive, Negative or zero. |
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| 28. |
The potential energy of a `1 kg` particle free to move along the x- axis is given by `V(x) = ((x^(4))/(4) - x^(2)/(2)) J` The total mechainical energy of the particle is `2 J` . Then , the maximum speed (in m//s) isA. `(3)/(sqrt2)m//s`B. `sqrt2m//s`C. `(1)/(sqrt2)m//s`D. `2 m//s` |
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Answer» Correct Answer - A At max. speed , `KE` is max. and `PE` is min. `PE` is min at `x=+-1` so `PE_(min)=-(1)/(4)` `KE_(max)=TE_(min)-PE_(min)rArr(1)/(2)mV_(max)^(2)=(9)/(4)rArrV_(max)=(3)/(sqrt2)m//s` |
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| 29. |
If the length of the tangent from (2, 5) to the circle x2 + y2 – 5x + 4y + k = 0 is √37 then find k. |
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Answer» Length of tangent = √S11 = √((2)2 + (5)2 - 5 x 2 + 4 x 5 + k) = 37 = 39 + k = – 2 units. |
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| 30. |
The projection of the vector(2i - j + k) on the vector(i - 2j + k) is(a) 4/√6 (b) 5/√6(c) 4/√3(d) 7/√6 |
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Answer» Answer is (b) 5/√6 |
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| 31. |
If |vector a| = √26, |vector b| = 7 and |vector(a x b)| = 35, then vector(a.b) = (a) 8(b) 7(c) 9(d) 12 |
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Answer» Answer is (b) 7 |
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| 32. |
If vector a = i + j + 2k and vector b = 3i + 2j - k, then the value of vector(a + 3b).(2a - b) = (a) 15(b) -15(c) 18(d) -18 |
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Answer» Answer is (b) -15 |
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| 33. |
If vector a = vector(i + j + 2k) and vector b = vector(3i + 2j - k) then the value of vector(a + 3b).(2a - b) is (a) 15(b) 18(c) -18(d) -15 |
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Answer» Answer is (c) - 18 |
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| 34. |
In the quadrilateral ABCD shown below, ∠A = ∠C = 90% ∠ABD = 45° ∠CDB = 60° and AB = 6cm.Find out the lengths of the other sides of the quadrilateral. |
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Answer» In ΔABD, The angles are 45°, 45°, 90° As the triangle is equilateral, sides are in the ratio, 1: 1: √2 AB = 6cm ∴ AD = 6cm, BD = 6√2cm \(CD=\frac{6\sqrt{2}}{2}=3\sqrt{2}\) \(BC=3\sqrt{2}\times\sqrt{3}=3\sqrt{6}\) |
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| 35. |
The base perimeter of a square pyramid is 48cm. Slant height is 10cm. Calculate lateral surface area and volume. |
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Answer» Base perimeter = 48cm baseedge = \(\frac{48}{4}\) = 12 cm, slant height = 10cm height = \(\sqrt{(10)^2-(6)^2}\) = \(\sqrt{64}\) = 8cm Curved siuface area= 2 × 12 × 10 = 240 cm2 Volume = \(\frac{1}{3}\) (12)2 × 8 = 384 cm3 |
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| 36. |
Prove that the ratio between the base edge, slant height and height of a square pyrarmid having equal edges is 2: √3 : √2. |
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Answer» Slant height = √3 a Height = \(\sqrt{(\sqrt{3a})^2-a^2}\) = \(\sqrt{2}a\) Base edge : Slant height : Height = 2a: √3a : √2 a = 2: √3 : √2 |
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| 37. |
A square pyramid is made from a solid cube having edge 30cm. Calculate the surface area. |
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Answer» Base edge of the square pyramid = 30 cm Height = 30 cm Slant height = \(\sqrt{30^2+15^2}\) = \(\sqrt{900+225}\) = \(\sqrt{1125}\) = \(15\sqrt{5}\) Lateral surface area = \(4\times\frac{1}{2}\times15\sqrt{2}\times30\) = 60 x 15√5 = 900√5 sq.cm Total surface area = 900 + 900√5 = 900(1 + √5) sq.cm |
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| 38. |
The base edge of a square pyramid is Stem, height 3cm. Calculate slant height and lateral edge |
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Answer» Base edge = 8 cm, height = 3 cm Slant height = \(\sqrt{(\frac{8}{2})^2+(3)^2}\) = \(\sqrt{16+9}\) = \(\sqrt{25}\) = 5 Length of lateral edge = \(\sqrt{(slant\,height)^2+(\frac{base\,edge}{2})^2}\) = \(\sqrt{(5)^2+4^2}{}\) = \(\sqrt{25+16}\) = \(\sqrt{41}\) cm |
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| 39. |
Prove that in any square pyramid, the squares of the height, slant height and lateral edge are in arithmetic sequence. |
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Answer» Height = h, Slant height = l, Lateral edge = e \(l^2=h^2+(a/2)^2-(1)\) \(l^2=e^2-(a/2)^2-(2)\) (1) + (2) : 2l2 = h2 + e2 \(l^2=\frac{h^2+e^2}{2}\) ∴ (h2, I2, e2) are in arithmetic sequence. |
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| 40. |
Is It possible to construct a pyramid of base edge 24 cm and lateral edge 13 cm? Justify |
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Answer» Since slant height is 5 cm, such a pyramid can’t be constructed. Slant height should be greater than half of the base edge. \(\sqrt{13^2-12^2}\) = 5 cm |
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| 41. |
The slant height of a square pyramid is 12 cm, lateral edge 13 cm. Calculate height |
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Answer» Slant height = 12 cm lateral edge = 13 cm \(\frac{base\,edge}{2}\) = \(\sqrt{(lateral\,edge)^2-(slant\,height)^2}\) = \(\sqrt{(13)^2-(12)^2}\) = \(\sqrt{169-144}\) = \(\sqrt{25}\) = 5 cm base edge = 10 cm Height = \(\sqrt{(12)^2-(5)^2}\) = \(\sqrt{119}\) cm |
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| 42. |
Two square pyramids have the same volume. The base edge of one is half that of the other. How many times the height of the second pyramid is the height of the first? |
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Answer» v1 = v2 \(\frac{1}{3}a^2_1h_1\) = \(\frac{1}{3}a^2_2h_2,\) \(\frac{1}{3}a^2h_1\) = \(\frac{1}{3}(\frac{a}{2})^2h_2\) \(\frac{1}{3}a^2h_1=\frac{1}{3}\times\frac{a^2}{4}\times h_2\) \(h_1=\frac{h_2}{4},\) 4h1 = h2 The height of the second pyramid is 4 times the height of the first pyramid. |
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| 43. |
The circular plate of radius 12cm is cut out into six sectors having same size. Calculate the slant height and radius of circular cone used to make one sector. |
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Answer» slant height = 12 cm centre angle = \(\frac{360}{60}=60\) radius of square pyramid = 12 × \(\frac{60}{360}\) = 2 cm |
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| 44. |
Surface area of a wooden sphere is 40 cm2. It is cut into two identical hemispheres. Find a. The area of the plane surface of one of the hemispheres, b. Its surface area. |
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Answer» a. Surface area of the sphere = 4 πr2 Here, 4 πr2 = 40cm2 πr2 = 10cm2 ∴ Area of plane surface = πr² = 10cm2 b. Surface area of one piece (hemisphere) = 3 πr2 = 3 x 10 = 30cm2 |
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| 45. |
The height of a square pyramid is 12cm, slant height 15cm , calculate total surface area and volume |
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Answer» height =12 cm. slant height = 15 cm a = \(2\sqrt{15^2-12^2}\) = 2 x 9 = 18 cm2 Total surface area = base- area + curved surface area = (18)2 + 2 × 18 × 15 = 324 + 540 = 864 cm2 Volume = \(\frac{1}{3}\)(18)2 x 12 = 1296 cm3 |
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| 46. |
The triangle given in the figure is one lateral face of a square pyramid.a. Calculate the slant height. b. Find the lateral surface area of the pyramid, |
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Answer» Slant height = \(\sqrt{17^2-8^2}\) = \(\sqrt{275}\) = 15 cm |
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| 47. |
The base edge of a square pyramid is 6cm, height 4cm, calculate slant height and total surface area. |
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Answer» Length of base edge = 6 cm, height = 4 cm, slant height = \(\sqrt{(3)^2+(4)^2}\) = \(\sqrt{9+16}\) = \(\sqrt{25}\) = 5 cm Total surface area = base area + curved surface area = (6)2 + 2 × 6 × 5 = 36 + 60 = 96 cm2 |
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| 48. |
Lateral surface of a square pyramid is shown in the Figure. All angles are equalFind the total length of all edges of the square: pyramid. Find the slant height What is the |atio between height and slant height |
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Answer» Sum of edges = 8 x 8 = 64 cm Slant height = 4√3 cm Height = \(\sqrt{(4\sqrt{3})^2-4^2}\) = \(\sqrt{18-16}\) = \(\sqrt{32}\) = \(4\sqrt{2}\) cm Ratio = \(\sqrt{3}:\sqrt{2}\) |
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| 49. |
A tent constructed in the form of a square pyramid of base perimeter 80 metres and lateral edge 26 metresa. Calculate the slant height of the tentb. Calculate the area of tarpaulin sheet. required to cover the lateral faces of the tent. |
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Answer» Base perimeter = 80 m, Base edge = 20 m Lateral edge = 26 m a. Slant height = \(\sqrt{26^2-10^2}\) = \(\sqrt{576}\) = 24 b. Lateral surface area = \(4\times\frac{1}{2}\times20\times24\) = 960 sq.metre |
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| 50. |
What is the ratio of the base-radius and slant height of a cone made by rolling up a semicircle? |
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Answer» Radius of bigger circle = R Radius of smaller circle = r Radius of circular base of the pyramid = r = \(\frac{R}{2}\) Ratio between radius and slant height \(r\div R=\frac{R}{2}:R=\frac{1}{2}:1=1:2\) |
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