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The radius of gyration of a rotating metallic disc is independent of the following physical quantity Position of axis of rotation Mass of disc Radius of disc Temperature of disc

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Moment of inertia of a body depends upon Distribution of mass of the body Position of axis of rotation Temperature of the body All are above

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Raw and boiled egg are made to spin on a smooth table by applying the same torque . The egg that spin faster is Raw egg Boiled egg Both will have same spin rate Difficult to predict

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A boiled egg and a raw egg of same mass and size are made to rotate about their own axis if 𝐼_1 and 𝐼_2 are moment of inertia of boiled egg and raw egg the 𝐼_1 = 𝐼_2 𝐼_1 < 𝐼_2 𝐼_1 > 𝐼_2 𝐼_1 =〖√2𝐼〗_2

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A uniform metal rod is rotated in horizontal plane about a vertical axis passing through its end at uniform rate . The tension in the rod is Same all point Different at different point and maximum at centre of rod Different at different point and minimum at axis of rotation Different at different point and maximum at axis of rotation

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2. 𝐼_1, 𝐼_2, are moment of inertia of two solid spheres of same mass about axes passing through their centres if first is made of wood and the second is made of steel then 𝐼_1 = 𝐼_2 𝐼_1 < 𝐼_2 𝐼_1 > 𝐼_2 𝐼_1 ≤ 𝐼_2

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The moment of inertia of a rigid body depends on A ) mass of body B) Position of axis of rotation C) Time period of its rotation D) Angular velocity of the body A and B are true B and C are true C and D are true A and D are true

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16. A positive charge ‘Q’ is fixed at a point . A negatively charged particle of mass ‘m’ and charge ‘q’ is revolving in a circular path of radius 𝑟_1 with Q as the centre . The work to be done to charge the radius of the circular path from 𝑟_1 to 𝑟_2 in joules is 0 𝑞𝑄/(4𝜋∈_0 ) [1/𝑟_1 −1/𝑟_2 ] 𝑞𝑄/(4𝜋∈_0 ) [1/𝑟_1 −1/𝑟_2 ] 1/𝑘 𝑞𝑄/(4𝜋∈_0 ) [1/𝑟_2 −1/𝑟_1 ]

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15. An insulated charged conducting sphere of radius 5cm has potential of 10v at the surface . What is the potential at centre? 10V ZERO Same as that at 5cm from the surface Same as that at 25cm from the surface

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14. Two positive charges 12𝜇C and 10 𝜇C are initially separated by 10cm . The work done in bringing the two charges 4cm closer is 7.2 J 3.6 J 8.4J 12.4J

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13.An electric cell does 5joules of work in carrying 10 coulombs of charge around a closed circuit . The emf of the cell is 2v 0.5v 4v 1v

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A positive point charge “q” is carried from a point “b” to a point A in the electric field of a point charge +Q . If the permittivity of free space is ∈_0 , the work done in the process is given by +Q………………A………………B

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11. Four charges +3𝜇C , - 1𝜇C , +5𝜇C and - 7𝜇C are arranged on the circumference of a circle of radius 0.5m. The potential at the centre is Zero 18x10^4V -18x10^4V 288x10^3V

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10. Two electric charges of 9𝜇C and - 3𝜇C are placed 0.16m apart in air .there are two points A and B on the line joining the two charges at distances of (a) 0.04m from -3 𝜇C and in between the charges and (b) 0.08m from - 3𝜇C and out side the two charges . The potentials at A and B are 0V ,5V 0V ,0V 5V ,0V 5V ,10V

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9.If 4x10^20eV is required to move a charge of 0.25C between two point , the potential difference between these two points is 256 volt 1/256 volt 256 x 10^(−19) volt 250volt

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8.Two electric charges of 10^(−9) C and 〖−10〗^(−9) C are placed at the corners A and B of an equilateral tringle ABC side 5cm . The electric intensity at C is 1800N/C 3600N/C 900N/C 2700N/C

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7. Two charges of 10𝜇C and -90 𝜇C are separated by a distance 24 cm . Electrostics field strength from the smaller charges is zero at a distance of 12cm 24cm 36cm 48cm

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6.The electric field at (30,30) cm due to a charge of -8nC at the origin in N𝐶^(−1) is -400(𝑖 ̂ +𝑗 ̂) 400(𝑖 ̂ +𝑗 ̂) -200√2(𝑖 ̂ +𝑗 ̂) 200√2(𝑖 ̂ +𝑗 ̂)

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5.An electron (m=9.1x10^(−31)kg) is sent into an electric field of intensity 9.1x10^6 N/c .The acceleration produced is 1.6x10^18 𝑚/𝑠^2 1.6x10^6 𝑚/𝑠^2 1.6x10^(−18) 𝑚/𝑠^2 1.6x10^(−6) 𝑚/𝑠^2

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4.Two equally charged pith balls 3cm apart repel each other with a force of 4x10^(−5)N . The charge on each ball is 2x10^9 C 2x10^(−9) C 2/3x10^9 C 2/3x10^(−9) C

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3. Two charges of +200𝜇C and -200𝜇C are placed at the corners B and C of an equilateral tringle ABC of side 0.1m . The force on a charge of 5 𝜇C placed a is 1800N 1200√3 N 600√3 N 900N

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2.Two charges each 1𝜇𝑐 are at p (2𝑖 ̂ +3𝑗 ̂ +𝑘 ̂) m and Q (𝑖 ̂ +𝑗 ̂ -𝑘 ̂) m . Then the force between them is …………………. 1.100N 2.10N 3.10^4 dyne 4.100 dyne

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1. A charge Q is divided into two parts 𝑞_1 and 𝑞_2 such that they experience maximum force of repulsion when separated by certain distance . The ratio of Q , 𝑞_1 and 𝑞_2 is 1:1:2 1:2:2 2:2:1 2:1:1

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Education is a part of Life