- Home
- Standard 12
- Physics
Assertion : A deuteron and an $\alpha -$ particle are placed in an electric field. If $F_1$ and $F_2$ be the forces acting on them and $a_1$ and $a_2$ be their accelerations respectively then, $a_1 = a_2$.
Reason : Forces will be same in electric field
If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
If Assertion is correct but Reason is incorrect.
If both the Assertion and Reason are incorrect.
Solution
$\mathrm{q}_{\mathrm{d}}=\mathrm{e}, \mathrm{m}_{\mathrm{d}}=2 \mathrm{m}_{\mathrm{p}}=2\, \mathrm{m}$
$\mathrm{q}_{\alpha}=2 \mathrm{e}, \mathrm{m}_{\alpha}=4 \mathrm{m}_{\mathrm{p}}=4 \,\mathrm{m}$
$\mathrm{F}_{1}=\mathrm{F}_{\alpha}=\mathrm{eE}, \mathrm{F}_{2}=\mathrm{F}_{\alpha}=2 \mathrm{eE} \neq \mathrm{F}_{1}$
Further, $\quad a_{1}=\frac{F_{1}}{2 m}=\frac{e E}{2 m}$
and $a_{2}=\frac{F_{2}}{2 m}=\frac{2 e E}{4 m}=\frac{e E}{2 m}=a_{1}$
