MCQ
Unit of radioactivity is Rutherford. Its value is
- A$3.7 \times {10^{10}}\,\,disintegrations/sec$
- B$3.7 \times {10^6}\,\,disintegrations/sec$
- C$1.0 \times {10^{10}}\,\,disintegrations/sec$
- ✓$1.0 \times {10^6}\,\,disintegrations/sec$
✓
Answer
Correct option: D.
$1.0 \times {10^6}\,\,disintegrations/sec$
d
(d)
(d)
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
A gas at $27^o C$ has a volume $V$ and pressure $P.$ On heating its pressure is doubled and volume becomes three times. The resulting temperature of the gas will be ...... $^oC$
→The dimension of where $\sqrt {\frac{\mu }{ \in }} $ is permeability $\& \varepsilon$ is permittivity is same as :
→A $P-$ type semiconductor can be obtained by adding
→A charge ${q_1}$ exerts some force on a second charge ${q_2}$. If third charge ${q_3}$ is brought near, the force of ${q_1}$ exerted on ${q_2}$
→A car runs at a constant speed on a circular track of radius $100\,m$ , taking $62.8\,sec$ for every circular lap. The average velocity and average speed for each circular lap respectively is
→A small coin is fixed at the centre of the base of an empty cylindrical steel container having radius $R=1 \,m$ and height $d=4 \,m$. At time $t=0$, the container starts getting filled with water at a flowrate of $Q=0.1 \,m ^3 / s$ without disturbing the coin.the approximate time .............. $s$ when the coin will first be seen by the observer $O$ from the height of $H=5.75 \,m$ above and $L=1.5 \,m$ radially away from the coin as shown in the figure. (Take, refractive index of water, $n=1.33$ )
→Primary side of a transformer is connected to $230 \mathrm{~V}, 50 \mathrm{~Hz}$ supply. Turns ratio of primary to secondary winding is $10: 1$. Load resistance connected to secondary side is $46\ \Omega$. The power consumed in it is :
→A block starts from rest at the top of frictionless slide at a height, $h_1$ above the ground. The block leaves the slide moving perfectly horizontally at a height $h_2$ above the ground. The block eventually hits the ground travelling at an angle $\theta = 30^o$ below the horizontal. Then
→The current density is a solid cylindrical wire of radius $R ,$ as a function of radial distance $r$ is given by $J ( r )= J _{0}\left(1-\frac{ r }{ R }\right) .$ The total current in the radial region $r =0$ to $r =\frac{ R }{4}$ will be
→A disk of radius $a / 4$ having a uniformly distributed charge $6 C$ is placed in the $x-y$ plane with its centre at $(-a / 2,0,0)$. A rod of length $a$ carrying a uniformly distributed charge $8 C$ is placed on the $x$-axis from $x=a / 4$ to $x=5 a / 4$. Two point charges $-7 C$ and $3 C$ are placed at $(a / 4,-$ $a / 4,0)$ and $(-3 a / 4,3 a / 4,0)$, respectively. Consider a cubical surface formed by six surfaces $x=\pm a / 2, y=\pm a / 2, z=\pm a / 2$. The electric flux through this cubical surface is
→