An electron accelerated through a potential difference V_1 has a … - Vidyadip

MCQ

An electron accelerated through a potential difference $V_1$ has a de-Broglie wavelength of $\lambda$. When the potential is changed to $V _2$, its de-Broglie wavelength increases by $50 \%$. The value of $\left(\frac{ V _1}{ V _2}\right)$ is equal to :

A
$3$
✓
$\frac{9}{4}$
C
$\frac{3}{2}$
D
$4$

✓

Answer

Correct option: B.

$\frac{9}{4}$

b
$KE =\frac{ P ^2}{2 m }, \quad P =\frac{ h }{\lambda}$

$eV _1=\frac{\left(\frac{ h }{\lambda}\right)^2}{2 m }$

$eV _2=\frac{\left(\frac{ h }{1.5 \lambda}\right)^2}{2 m }$

$\frac{ V _1}{ V _2}=(1.5)^2=\frac{9}{4}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

JEE STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

Two metal spheres of radius $R$ and 3R have same surface charge density $\sigma$. If they are brought in contact and then separated, the surface charge density on smaller and bigger sphere becomes $\sigma_{1}$ and $\sigma_{2}$, respectively. The ratio $\frac{\sigma_{1}}{\sigma_{2}}$ is

When acceleration of $5\ kg$ block is $2\ m/s^2$ as shown in figure, then what will be the acceleration of $15\ kg$ block ............ $m/s^2$

Two particles of equal mass $(m)$ each move in a circle of radius $(r)$ under the action of their mutual gravitational attraction. Find the speed of each particle

Two concentric hollow conducting spheres of radius $r$ and $R$ are shown. The charge on outer shell is $Q$. What charge should be given to inner sphere so that the potential at any point $P$ outside the outer sphere is zero?

An object is moving through the liquid. The viscous damping force acting on it is proportional to the velocity. Then dimension of constant of proportionality is

Two wires each of radius $0.2\,cm$ and negligible mass, one made of steel and other made of brass are loaded as shown in the figure. The elongation of the steel wire is $.........\times 10^{-6}\,m$. [Young's modulus for steel $=2 \times 10^{11}\,Nm ^{-2}$ and $g =10\,ms ^{-2}$ ]

The orbital speed of Jupiter is

Carnot heat engine works with an ideal diatomic gas and an adiabatic volume expansion ratio $32$ . Then its efficiency is ....... $\%$

Which of the following is correct, when a person walks on a rough surface

For a particle executing $S.H.M.$ the displacement $x$ is given by $x = A\cos \omega t$. Identify the graph which represents the variation of potential energy $(P.E.)$ as a function of time $t$ and displacement $x$