Monochromatic radiation emitted when electron on hydrogen atom ju… - Vidyadip

MCQ

Monochromatic radiation emitted when electron on hydrogen atom jumps from first excited to the ground state irradiates a photosensitive material. The stopping potential is measured to be $3.57 \;V$. The threshold frequency of the material is .........$ \times 10^{15}\; Hz$

A
$2.5$
✓
$1.6$
C
$4$
D
$5$

✓

Answer

Correct option: B.

$1.6$

b
Energy released from emmition of electron is $E =(-3.4)-(-13.6)=10.2 eV$.

From photo-electric equation, work function $\phi= E - eV = h v _0$

On Solving this $v _0=1.6 \times 10^{15} Hz$

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

The third line of Balmer series of an ion equivalent to hydrogen atom has wavelength of $108.5\, nm.$ The ground state energy of an electron of this ion will be.....$eV$

Two charges $+q$ and $-q$ are placed at a distance $b$ apart as shown in the figure given below.The electric field at a point $P$ on the perpendicular bisector as shown is

Cohesive force is experienced between

In Young's double slit experiment, the distance between the two slits is $0.1 \,mm$, the distance between the slits and the screen is $1 \,m$ and the wavelength of the light used is $600 \,nm$. The intensity at a point on the screen is $75 \%$ of the maximum intensity. smallest distance ................ $\,mm$ of this point from the central fringe

For a particle moving under the action of a variable force, kinetic energy-position graph is given, then

A block of mass $5 kg$ is at rest on a rough inclined surface. If angle of inclination of plane is $60^{\circ}$, then force applied by it on block is .......... $N$

Imagine earth to be a solid sphece of mass $M$ and radius $R$. If the value of acceleration due to gravity at a depth d below earth's surface is same as its value at a height $h$ above its surface and equal to $\frac{g}{4}$ (where $g$ is the value of acceleration due to gravity on the surface of earth), the ratio of $\frac{h}{d}$ will be

This question has Statement $1$ and Statement $2.$ Of the four choices given after the Statements, choose the one that best describes the two Statements.

Statement $1 :$ An inventor claims to have constructed an engine that has an efficiency of $30\%$ when operated between the boiling and freezing points of water. This is not possible.

Statement $2:$ The efficiency of a real engine is always less than the efficiency of a Carnot engine operating between the same two temperatures.

The refractive index of water is $4 / 3$ and that of glass is $5/3$. What will be the critical angle for the ray of light entering water from the glass

If a radioactive material remains $25 \%$ after $16$ days, then its half life will be ......... days