Electromagnetism
Current Electricity
MCQ (Single Correct Answer)
Moving Charges and Magnetism
MCQ (Single Correct Answer)
Magnetism and Matter
MCQ (Single Correct Answer)
Electromagnetic Induction
MCQ (Single Correct Answer)
Alternating Current
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Electromagnetic Waves
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Modern Physics
Dual Nature of Radiation
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Semiconductor Devices and Logic Gates
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Communication Systems
MCQ (Single Correct Answer)
1
COMEDK 2020
MCQ (Single Correct Answer)
+1
-0

Two radioactive materials X$$_1$$ and X$$_2$$ have decay constant 5$$\lambda$$ and $$\lambda$$, respectively. If initially they have the same number of nuclei, then the ratio of the number of nuclei of X$$_1$$ to X$$_2$$ will be $$1/e$$ after a time

A
$$1/4\lambda$$
B
$$e/\lambda$$
C
$$\lambda$$
D
$$\frac{1}{2}\lambda$$
COMEDK Subjects