An ionisation chamber, with parallel conducting plates as anode and cathodes has $5 \times {10^7}{\rm{\;c}}{{\rm{m}}^{ - 3}}$ electrons and the same number of singly charged positive ions per ${\rm{c}}{{\rm{m}}^3}$. The electrons are moving toward the anode with velocity 0.4${\rm{m}}{{\rm{s}}^{ - 1}}$. The current density from anode to cathode is $4{\rm{\mu A}}{{\rm{m}}^{ - 2}}.$ The velocity of positive ions moving towards cathode is

$0.1\;{\rm{m}}{{\rm{s}}^{ - 1}}$

$0.4\;{\rm{m}}{{\rm{s}}^{ - 1}}$

$1.6\;{\rm{m}}{{\rm{s}}^{ - 1}}$

NEET UG PHYSICS MCQ: DUAL NATURE OF RADIATION AND MATTER

1 Hard

1 of 1

Application +4 | -1

An ionisation chamber, with parallel conducting plates as anode and cathodes has

5 \times {10^7}\mathrm{\;c}{\mathrm{m}^{ - 3}}

electrons and the same number of singly charged positive ions per

\mathrm{c}{\mathrm{m}^3}

. The electrons are moving toward the anode with velocity 0.4

\mathrm{m}{\mathrm{s}^{ - 1}}

. The current density from anode to cathode is

4\mathrm{\mu A}{\mathrm{m}^{ - 2}}.

The velocity of positive ions moving towards cathode is

View answer and explanation

Correct option: A

0.1\;\mathrm{m}{\mathrm{s}^{ - 1}}

Option A (

0.1\;\mathrm{m}{\mathrm{s}^{ - 1}}

) is correct because it is the velocity of the positive ions calculated using the current density and the electron velocity.