NEET-XII-Physics
11: Gravitation
- #21The gravitational field in a region is given by
E=2i→+3j→ N kg-1. Show that no work is done by the gravitational field when 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.]Ans : The gravitational field in a region is given by `` \stackrel{\to }{\,\mathrm{\,E\,}}=2\stackrel{‸}{i}+3\stackrel{‸}{j}``.
Slope of the electric field, `` {m}_{1}=\,\mathrm{\,tan\,}{\,\mathrm{\,\theta \,}}_{1}=\frac{3}{2}``
The given line is 3y + 2x = 5.
Slope of the line, `` {m}_{2}=\,\mathrm{\,tan\,}{\,\mathrm{\,\theta \,}}_{2}=-\frac{2}{3}``
We can see that m1m2 = -1
Since the directions of the field and the displacement are perpendicular to earth other, no work is done by the gravitational field when a particle is moved on the given line.
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