Engineering QuestionsPhysics

155 solved questions with detailed explanations

41

Q.40. Two known resistance of R and 2R and one unknown resistance X are connected in a circuit as shown in the figure. If the equivalent resistance between points A and B in the circuit is X , then

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Q.50. A tube is filled with water and a wooden cube 10 cm 10cm 10cm is placed in the water. The wooden cube is found to float on the water with a part of it submerged in water. When a metal coin is

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Q.41. Refer the figure given below. and are refractive indices of air and lens material. The height of image will be _______ cm. [Figure: A plano-convex lens with object and image distances].

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Q.49. When an external resistance of is connected across terminals of a cell, a current of 0.25 A flows through it. When the resistor is replaced by a resistor, a current of 0.5 A flows through it.

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Q.41. A spherical interface lens of radius R separates two media of refractive indices 1 and 1.4 respectively as shown in the figure below. A point source is placed at a distance of 4R in front of sph

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Q.41. An object AB is placed 15 cm on the left of a convex lens P of focal length 10 cm. Another convex lens Q is now placed 15 cm right of lens P. If the focal length of lens Q is 15 cm, the final im

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Q.32. A parallel plate air capacitor has a capacitance C. When it is half filled as show in figure with a dielectric constant K = 5, the percentage increase in the capacitance is [Figure: A parallel p

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48

Q.47. A gun mounted on the ground fires bullets in all directions with same speed. The farthest distance the bullets could reach is 6.4 m. The speed of the bullets from the gun is __________ m/s. (tak

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Q.45. In a semiconductor p-n diode, the doping concentrations on p-side and n-side are atoms/cm³ and atoms/cm³, respectively. Which one of the following statement is true?

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Q.31. A metal string A is suspended from a rigid support and its free end is attached to a block of mass M. Second block having mass 2M is suspended at the bottom of the first block using a string B.

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Q.48. A series LCR circuit with , H and is connected to a variable frequency a.c. source. The inductive reactance at resonant frequency is .

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Q.30. A wheel initially at rest is subjected to a uniform angular acceleration about its axis. In the first 2 s it rotates through an angle . In the next 2 s it rotates through an angle . The ratio i

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Q.42. Light ray incident along a vector AO(AO=2\hat{i}-3\hat{j}) emerges out along vector OB(OB=C\hat{i}-4\hat{j}) as shown in the figure below. The value of C is

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Q.38. Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : In electrostatics, a conductor does not store any net charge inside. Reason R

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Q.39. A river of width 200 m is flowing from west to east with a speed of 18 km/h. A boat, moving with speed of 36 km/h in still water, is made to travel one-round trip (bank to bank of the river). Mi

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Q.35. One gas of mole of molecules at temperature , volume , and pressure , and another gas of mole of molecules at temperature , volume , and pressure , are mixed resulting in pressure P and volume

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Q.43. An electron is travelling with a velocity v in free space and when it enters a medium, its velocity is reduced by 20%. The de Broglie wavelength of electron in the medium is , where is its de B

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Q.42. The maximum intensity in a Young's double slit experiment is . Distance between the slits (d) is , where is the wavelength of light used. The intensity of the fringe, exactly opposite to one of

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Q.36. An ideal gas undergoes a process maintaining relation between pressure (P) and volume (V) as , where and are constants. If two samples A and B (two moles each) with initial volume and respec

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Q.38. A thin half ring of radius 35 cm is uniformly charged with a total charge of Q coulomb. If the magnitude of the electric field at centre of the half ring is 100 V/m, then the value of Q is ____

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