Question 24

Define electric flux. Is it a scalar or a vector quantity? A point charge q is at a distance d/2 directly above the centre of a square of side ‘d’, as shown in the figure. Use Gauss’s law to obtain the expression for the electric flux through the square.

(b) If the point charge is now moved to a distance ‘d’ from the centre of the square and the side of the square is doubled, explain how the electric flux be affected.

Answer

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(a) Find the distance of the third bright fringe on the screen from the central maximum for wavelength 650 nm.

(b) What is the least distance from the central maximum where the bright fringes due to both the wavelengths coincide?

- Q:- ">
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- Q:- ">
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^{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?

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