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Can two like charged bodies attract each other explain?

Important Questions on Electrostatics

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

A neutral spherical copper particle has a radius of

10 nm (1 nm = 10^{- 9} m)

. It gets charged by applying the voltage slowly adding one electron at a time. Then, the graph of the total charge on the particle versus the applied voltage would look like

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

Two identical conducting spheres A and B carry equal charge. They are initially separated by a distance much larger than their diameters and the force between them is F. A third identical conducting sphere C is uncharged. Sphere C is first touched to A, then to C and removed. As a result, the force between A and B now is

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

Two isolated conducting spheres

S_{1}

and

S_{2}

of radius

\frac{2}{3} R

and

\frac{1}{3} R

have

12 μ C

and

- 3 μ C

charges, respectively, and are at a large distance from each other, They are now connected by a conducting wire. A long time after this is done the charges on

S_{1}

and

S_{2}

are respectively:

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

Two insulated charged spheres of radii

20 c m

and

25 c m

, respectively, and having an equal charge

Q

are connected by a copper wire. Then, they are separated. Which of the following is correct ?

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

In a system used for spraying cars, a car body is positively charged. Neutral droplets of paint are then attracted to the car because the positive car body induces a charge on the droplets of paint. Which diagram best shows the charge pattern?

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

A neutral metallic sphere is placed near a negative point charge (outside the sphere). The net charge on sphere, then

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Which of the following cannot be charged easily by friction?

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

A comb runs through one's dry hair attracts small bits of paper. This is due to

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

Suppose there are two copper spheres

A

and

B

having identical sizes. The distance between the centers of sphere is

50 cm

and the charge on each sphere is

6.5 \times 10^{- 7} C

. A third sphere of the same size but uncharged is brought in contact with the first, then brought in contact with the second, and finally removed from both. What is the new force of repulsion between

A

and

B

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

In a system used for spraying cars, a car body is positively charged. Neutral droplets of paint are then attracted to the car because the positive car body induces charge on the droplets of paint. Which diagram best shows the charge pattern?

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

Five Styrofoam balls are suspended from insulating threads. Several experiments are performed on the balls and the following observations are made -

(i) Ball A repels C and attracts B

(ii) Ball D attracts B and has no effect on E

(iii) A negatively charged rod attracts both A and E.

An electrically neutral Styrofoam ball gets attracted if placed nearby a charged body due to induced charge. What are the charges, if any, on each ball

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Which of the following diagram is correct ?

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

The diagram shows an earthed conducting sphere held close to a positively charged dome.

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What is the charge and potential of the conducting sphere?

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

A table tennis ball, covered with conducting paint, is suspended by a silk thread so that it hang between two plates. Out of these, one is earthed and other is connected to a high voltage generator. This ball,

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

The energy spectrum of a black body exhibits a maximum around a wavelength

λ_{0} .

The temperature of the black body is now changed such that the energy is maximum around a wavelength

\frac{{3 λ}_{0}}{4}

. The power radiated by the black body will now increase by a factor of

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

Assertion: If there exists coulomb attraction between two bodies both of them may not be charged.

Reason: In coulomb attraction two bodies are oppositely charged.

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Physics>Electricity and Magnetism>Electrostatics>Methods of Charging

Two identical metal spheres