Using a nuclear counter the count rate of emitted particles from … - Vidyadip

MCQ

Using a nuclear counter the count rate of emitted particles from a radioactive source is measured. At $t = 0$ it was $1600$ counts per second and $t = 8\, seconds$ it was $100$ counts per second. The count rate observed, as counts per second, at $t = 6\, seconds$ is close to

✓
$200$
B
$150$
C
$400$
D
$360$

✓

Answer

Correct option: A.

$200$

a
In $8$ seconds count rate becomes $\frac{1}{16}$ times.

$\therefore $ $4 $ half lives $=8\,s$

$1$ half lie $=2 \mathrm{s}$

In $6 \mathrm{s}$ or $3$ half lives, count rate $=\frac{1600}{2^{3}}=200$

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

Maximum useable frequency $(MUF)$ in $F$ -region layer is $x$ , when the critical frequency is $60 \,MHz$ and the angle of incidence is $70°$. Then $x$ is.......$MHz$

A ray of light is incident on the surface of a glass plate at an angle of incidence equal to Brewster's angle $\phi $. If $\mu $ represents the refractive index of glass with respect to air, then the angle between reflected and refracted rays is

Two bodies of the same mass are moving with the same speed, but in different directions in a plane. They have a completely inelastic collision and move together thereafter with a final speed which is half of their initial speed. The angle between the initial velocities of the two bodies (in degree) is.

For the given combination of gates, if the logic states of inputs $ A, B, C$ are as follows $A = B = C = 0$ and $A = B = 1, C = 0$ then the logic states of output $D $ are

A body, under the action of a force $\vec F = 6\hat i - 8\hat j + 10\hat k,$ acquires an acceleration of $1\, m/s^2$ The mass of this body must be

If Gravitational constant is decreasing in time, what will remain unchanged in case of a satellite orbiting around earth

Ten one-rupeed coins are put on top of each other on a table. Each coin has mass $m$. The reaction of the $6^{th}$ coin (counted from the bottom) on the $7^{th}$ coins is .......... $mg$

In the adjoining circuit, the battery $E_1$ has an emf of $12\, volt$ and zero internal resistance while the battery $E_2$ has an $emf$ of $2\, volt$. If the galvanometer $G$ reads zero, then the value of the resistance $X$ (in $ohm$ ) is

The kinetic energies of a planet in an elliptical orbit about the Sun, at positions $A, B$ and $C$ are $K_A, K_B$ and $K_C$, respectively. $AC$ is the major axis and $SB$ is perpendicular to $AC$ at the position of the Sun $S$ as shown in the figure. Then

A glass prism of refractive index $1.5$ is immersed in water (refractive index $\frac {4}{3}$ ) as shown in figure. A light beam incident normally on the face $AB$ is totally reflected to reach the face $BC,$ if