AIEEE 2004 | Electrostatics Question 211 | Physics

A charged oil drop is suspended in a uniform field of $$3 \times {10^4}$$ $$v/m$$ so that it neither falls nor rises. The charge on the drop will be (Take the mass of the charge $$ = 9.9 \times {10^{ - 15}}\,\,kg$$ and $$g = 10\,m/{s^2}$$)

$$1.6 \times {10^{ - 18}}\,C$$

$$3.2 \times {10^{ - 18}}\,C$$

$$3.3 \times {10^{ - 18}}\,C$$

$$4.8 \times {10^{ - 18}}\,C$$

AIEEE 2003

MCQ (Single Correct Answer)

-1

If the electric flux entering and leaving an enclosed surface respectively is $${\phi _1}$$ and $${\phi _2},$$ the electric charge inside the surface will be

$$\left( {{\phi _2} - {\phi _1}} \right){\varepsilon _0}$$

$$\left( {{\phi _2} + {\phi _1}} \right)/{\varepsilon _0}$$

$$\left( {{\phi _1} - {\phi _2}} \right)/{\varepsilon _0}$$

$$\left( {{\phi _1} + {\phi _2}} \right){\varepsilon _0}$$

AIEEE 2003

MCQ (Single Correct Answer)

-1

A thin spherical conducting shell of radius $$R$$ has a charge $$q.$$ Another charge $$Q$$ is placed at the center of the shell. The electrostatic potential at a point $$P$$ a distance $${R \over 2}$$ from the center of the shell is

$${{2Q} \over {4\pi {\varepsilon _0}R}}$$

$${{2Q} \over {4\pi {\varepsilon _0}R}} - {{2q} \over {4\pi {\varepsilon _0}R}}$$

$${{2Q} \over {4\pi {\varepsilon _0}R}} + {q \over {4\pi {\varepsilon _0}R}}$$

$${{\left( {q + Q} \right)2} \over {4\pi {\varepsilon _0}R}}$$

AIEEE 2003

MCQ (Single Correct Answer)

-1

Three charges $$ - {q_1}, + {q_2}$$ and $$ - {q_3}$$ are placed as shown in the figure. The $$x$$-component of the force on $$ - {q_1}$$ is proportional to AIEEE 2003 Physics - Electrostatics Question 211 English