Solveeit Logo
Login

Question

Question: What is the magnitude of a point charge due to which the electric field 30 cm away has the magnitude...

What is the magnitude of a point charge due to which the electric field 30 cm away has the magnitude 2 newton/coulomb[1/4πε0=9×109Nm2]\lbrack 1/4\pi\varepsilon_{0} = 9 \times 10^{9}Nm^{2}\rbrack

A

2×10−11coulomb2 \times 10^{- 11}coulomb

B

3×10−11coulomb3 \times 10^{- 11}coulomb

C

5×10−11coulomb5 \times 10^{- 11}coulomb

D

9×10−11coulomb9 \times 10^{- 11}coulomb

Answer

2×10−11coulomb2 \times 10^{- 11}coulomb

Explanation

Solution

By using E=14πε0.Qr2E = \frac{1}{4\pi\varepsilon_{0}}.\frac{Q}{r^{2}}; 2=9×109×Q(30×10−2)2⇒Q=2×10−11C2 = 9 \times 10^{9} \times \frac{Q}{\left( 30 \times 10^{- 2} \right)^{2}} \Rightarrow Q = 2 \times 10^{- 11}C