Question 13

A cube of side *b* has a charge *q* at each of its vertices. Determine the potential and electric field due to this charge array at the centre of the cube.

Answer

Length of the side of a cube = *b *

Charge at each of its vertices = *q*

A cube of side *b* is shown in the following figure.

d = Diagonal of one of the six faces of the cube

l = Length of the diagonal of the cube

The electric potential (V) at the centre of the cube is due to the presence of eight charges at the vertices.

Therefore, the potential at the centre of the cube is

The electric field at the centre of the cube, due to the eight charges, gets cancelled. This is because the charges are distributed symmetrically with respect to the centre of the cube. Hence, the electric field is zero at the centre.

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^{−7}C.(a) Estimate the number of electrons transferred (from which to which?)

(b) Is there a transfer of mass from wool to polythene?

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What is the force between two small charged spheres having charges of 2 x 10

^{-7}C and 3 x 10^{-7}C placed 30 cm apart in air? - Q:-
A point charge +10 μC is a distance 5 cm directly above the centre of a square of side 10 cm, as shown in Fig. 1.34. What is the magnitude of the electric flux through the square? (Hint: Think of the square as one face of a cube with edge 10 cm.)

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A parallel plate capacitor with air between the plates has a capacitance of 8 pF (1pF = 10

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A 600 pF capacitor is charged by a 200 V supply. It is then disconnected from the supply and is connected to another uncharged 600 pF capacitor. How much electrostatic energy is lost in the process?

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^{-8}C and -3 x 10^{-8}C are located 16 cm apart. At what point(s) on the line joining the two charges is the electric potential zero? Take the potential at infinity to be zero. - Q:-
A 12 pF capacitor is connected to a 50V battery. How much electrostatic energy is stored in the capacitor?

- Q:-
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^{4}N/C at a distance of 2 cm. Calculate the linear charge density. - Q:- A circular coil of wire consisting of 100 turns, each of radius 8.0 cm carries a current of 0.40 A. What is the magnitude of the magnetic field B at the centre of the coil?
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- Q:-
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- Q:-
Consider a uniform electric field E = 3 × 10

^{3}îN/C.(a) What is the flux of this field through a square of 10 cm on a side whose plane is parallel to the yz plane?

(b) What is the flux through the same square if the normal to its plane makes a 60° angle with the x-axis?

Shaikh tayyab
2019-10-23 22:08:18

Thanks

Sayoni
2019-10-02 18:32:46

Thanks

Anubhav
2019-09-15 00:34:09

I don't think the electric field at the centre will be zero. Because if the electric field at the the centre is zero then the force on any test charge placed at the centre is also zero (F=QE), and this would mean that you can actually confine a charge inside the cube. This is not true (Earnshaw's theorem).

Aiswariya
2019-07-18 21:47:18

Thanks

malu
2019-07-03 20:39:18

âââ

Rohini
2019-06-27 19:43:10

Tnq

Abhishek meena
2019-06-05 16:26:01

Thanks ðððð

Akash
2019-04-17 20:28:08

Thanks

Bibekananda sahoo
2019-02-18 21:33:21

Thank you very much.

Himanshu
2018-12-22 21:32:59

Thanks

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