The force of interaction between two atoms is given by $F\, = \,\alpha \beta \,\exp \,\left( { - \frac{{{x^2}}}{{\alpha kt}}} \right);$ where $x$ is the distance, $k$ is the Boltzmann constant and $T$ is temperature and $\alpha $ and $\beta $ are two constants. The dimension of $\beta $ is
  • A$M^0L^2T^{-4}$
  • B$M^2LT^{-4}$
  • C$MLT^{-2}$
  • D$M^2L^2T^{-2}$
JEE MAIN 2019, Diffcult
Download our app for free and get startedPlay store
Power of $e$ should be dim ensionless.
So,$\left[ \lambda \right] = \left( {\alpha Tk} \right)$
$\Rightarrow \,{L^2} = \left[ \alpha \right]\left( {M{L^2}{T^{ - 2}}} \right)$
$\Rightarrow \left( \alpha \right) = \left( {{M^{ - 1}}{T^2}} \right)$
$\Rightarrow \,E = \frac{1}{2}KT$
$\Rightarrow \left( {M{L^2}{T^{ - 2}}} \right)\left( E \right) = \left[ {KT} \right]$
$\Rightarrow \left( {\alpha \beta } \right) = \left( F \right)$
$\Rightarrow \left( {{M^{ - 1}}{T^2}} \right)\left( \beta \right) = \left( {ML{T^{ - 2}}} \right)$
art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    If the constant of gravitation $(G)$, Planck's constant $(h)$ and the velocity of light $(c)$ be chosen as fundamental units. The dimension of the radius of gyration is
    View Solution
  • 2
    $M{L^{ - 1}}{T^{ - 2}}$ represents
    View Solution
  • 3
    The dimensional formula of angular velocity is
    View Solution
  • 4
    A unitless quantity?
    View Solution
  • 5
    A beaker contains a fluid of density $\rho \ kg / m^3$, specific heat $S J / \ kg^oC$ and viscosity $\eta $. The beaker is filled upto height $h$. To estimate the rate of heat transfer per unit area $(Q / A)$ by convection when beaker is put on a hot plate, a student proposes that it should depend on $\eta ,\left( {\frac{{S\Delta \theta }}{h}} \right)$ and $\left( {\frac{1}{{\rho g}}} \right)$ when $\Delta \theta ($ in $^\circ C)$ is the difference in the temperature between the bottom and top of the fluid. In that situation the correct option for $(Q / A)$ is
    View Solution
  • 6
    The length and width of a rectangular room are measured to be $3.95 \pm 0.05 \,m$ and $3.05 \pm 0.05 \,m$, respectively. The area of the floor is .................... $m^2$
    View Solution
  • 7
    Find the value of $\frac{1.53 \times 0.9995}{1.592}$ with due regard for significant figures
    View Solution
  • 8
    The nuclear cross-section is measured in barn, it is equal to
    View Solution
  • 9
    The velocity of water waves $v$ may depend upon their wavelength $\lambda $, the density of water $\rho $ and the acceleration due to gravity $g$. The method of dimensions gives the relation between these quantities as
    View Solution
  • 10
    We can reduce random errors by
    View Solution