Q. 21

# The gravitational field in a region is given by E = (2i + 3j)Nkg^{-1}. Show that no work is done by the gravitational field whom a particle is moved on the line 3y +2x = 5.

[Hint: if a line y=mx + c makes angle θ with the X – axis, m= tan θ]

Answer :

The electric field is given by

The angle made by the electric field with the x axis is

The line is given by

Hence, the angle made by the line with the x-axis is

Now,

Hence, The angle between the electric filed and the line is .

Hence, there’s no component of electric field along the line and no work would be done by this field.

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