Question

A Charged sphere of radius 1m carries a charge of 1 x 10-9 C. The electric fields at a point P, which is at a distance d = 3m from the centre of the sphere and at a point Q, at a distance d = 0.3m from the centre of the sphere are respectively a) 1 N/C and 100 N/C b) 1 N/C and zero c) zero and 1 N/C d) 1 N/C and 3 N/C

Answer 1

a) 1 N/C and 100N/C

Explanation:

E=kq/r^2

E=1/4π ephsilon q/r^2

1/4π ephsilon value=9×10^9

So substituting,

For d=3

E=9×10^9×1×10^-9/3×3

E=1 N/C

For d=0.3

E=9×10^9×1×10^-9/0.3×0.3

E=100 N/C

Answer 2

Answer:

A

Explanation:

Here we have to find electric fields at d=3m,and d=0.3m

Given

A Charged sphere of radius 1m carries a charge (Q) =

1 x 10-9 C

At a distance d=3m

$e = \frac{kq}{{r}^{2} }$

$k = \frac{1}{(4\pi)e} = 9 \times {10}^{9}$

$electricfield = \frac{9 \times {10}^{9} \times {10}^{ - 9} }{3 \times 3}$

$= 1$

electric field at a distance 3m is 1N/c

At distance d=0.3m

$e = \frac{kq}{{r}^{2} }$

$\frac{9 \times {10}^{9} \times {10}^{ - 9} }{0.3 \times 0.3} = 100$

electric field at a distance 0.3m is 100N/c

#SPJ2