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In forward biasing of the p-n junction:
Identify the equivalent logic gate represented by the circuit given below:
In the nuclear decay given below: $$ _{Z}^{A}X \rightarrow _{Z+1}^{A}Y \rightarrow _{Z-1}^{A-4}B^* \rightarrow _{Z-1}^{A-4}B $$ The particles emitted in the sequence are:
Which of the following statements is true for nuclear forces?
Two nuclei have their mass numbers in the ratio of 1:3. The ratio of their nuclear densities would be:
The rate of radioactive disintegration at an instant for a radioactive sample of half-life $2.2 \times 10^9 \text{ s}$ is $10^{10} \text{ s}^{-1}$. The number of radioactive atoms in that sample at that instant is:
What is the radius of iodine atom? (atomic no. 53, mass no. 126)
What happens to the mass number and the atomic number of an element when it emits $\gamma$-radiation?
If a nucleus $_n X^m$ emits one $\alpha$ and two $\beta$ particles, the resulting nucleus will be:
A human body required the $0.01\text{ Curie}$ activity of a radioactive substance after $24\text{ hours}$. The half-life of the radioactive substance is $6\text{ hours}$. The maximum activity of the radioactive substance that can be injected will be:
The binding energy per nucleon of ${}_{3}^{7}Li$ and ${}_{2}^{4}He$ nuclei are $5.60 \text{ MeV}$ and $7.06 \text{ MeV}$, respectively. In the nuclear reaction ${}_{3}^{7}Li + {}_{1}^{1}H \rightarrow {}_{2}^{4}He + {}_{2}^{4}He + Q$, the value of energy Q released is:
The power obtained in a reactor using U-235 disintegration is 1000 kW. The mass decay of U-235 per hour is:
Fusion reaction takes place at high temperature because:
The numbers of nuclei of a radioactive substance at time t = 0 are 1000 and 900 at time t = 2 sec. Then the number of nuclei at time t = 4 sec will be:
If the nuclear radius of ${}^{27}\mathrm{Al}$ is 3.6 Fermi, the approximate nuclear radius of ${}^{64}\mathrm{Cu}$ in Fermi is:
Out of the following which one is a forward-biased diode?
10 g of radioactive material of half-life 15 year is kept in store for 20 years. The disintegrated material mass is
Two radioactive nuclei P and Q, in a given sample decay into a stable nucleus R. At time t = 0, the number of P species are 4N_0 and that of Q is N_0. Half-life of P (for conversion to R) is 1 min whereas that of Q is 2 min. Initially there are no nuclei of R present in the sample. When number of nuclei of P and Q are equal, the number of nuclei of R present in the sample would be:
After two hours, one-sixteenth of the starting amount of a certain radioactive isotope remained undecayed. The half life of the isotope is
For radioactive material, the half-life is 10 minutes. If initially, there are 600 number of nuclei, the time taken (in minutes) for the disintegration of 450 nuclei is: