MCQ
$\gamma$-rays radiation can be used to create electron-positron pair. In this process of pair production, $\gamma$-rays energy cannot be less than .......$MeV$
- A$5$
- B$4.02$
- C$15$
- ✓$1.02 $
✓
Answer
Correct option: D.
$1.02 $
d
(d) Energy released by $\gamma - $ rays for pair production must be greater than $1.02\, MeV.$
(d) Energy released by $\gamma - $ rays for pair production must be greater than $1.02\, MeV.$
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
Two sources of equal $emf$ are connected to an external resistance $R$. The internal resistances of the two sources are ${R_1}$ and ${R_2}\,({R_2} > {R_1})$. If the potential difference across the source having internal resistance ${R_2}$ is zero, then
→In a series $L-C-R$ circuit, $C = 10^{-11}\,Farad.$ $L = 10^{-5}\,Henry$ and $R =100\,Ohm.$ when a constant $D.C.$ voltage $E$ is applied to the circuit, the capacitor acquires a charge $10^{-9}\,C$ .The $D.C.$ source is replaced by a sinusoidal voltage source in which the peak voltage $E_0$ is equal to the constant $D.C.$ voltage $E.$ At resonance the peak value of the charge acquired by the capacitor will be
→Consider an infinite matrix of capacitors as shown in the figure. The effective capacitance between point $A$ and $B$ will be
→In the circuit shown in the figure, the ratio of the quality factor and the band width is $.............$ s.
→Suppose we consider a large number of containers each containing initially $10000$ atoms of a radioactive material with a half life of $1$ year. After $1$ year:
→A red $LED$ emits light at $0.1$ watt uniformly around it. The amplitude of the electric field of the light at a distance of $1\ m$ from the diode is....$ Vm^{-1}$
→In the Davisson and Germer experiment, the velocity of electrons emitted from the electron gun can be increased by?
Out of the following statements which is not correct
How many $60 \,W$ bulbs may be safely run on $220 \,V$ using a $5 \,A$ fuse is .........
→A galvanometer has a resistance of $50\ \Omega$ and it allows maximum current of $5 \mathrm{~mA}$. It can be converted into voltmeter to measure upto $100 \mathrm{~V}$ by connecting in series a resistor of resistance
→