NEET Exam  >  NEET Questions  >  After 300 days, the activity of a radioactive... Start Learning for Free
After 300 days, the activity of a radioactive sample is 5000 dps (disintegrations per sec). The activity becomes 2500 dps after another 150 days. The initial activity of the sample in dps is
  • a)
    20,000    
  • b)
    10,000
  • c)
    7,000    
  • d)
    25,000
Correct answer is option 'A'. Can you explain this answer?
Most Upvoted Answer
After 300 days, the activity of a radioactive sample is 5000 dps (disi...
Calculation of Initial Activity of the Sample

Given,

Activity after 300 days = 5000 dps

Activity after another 150 days = 2500 dps

Let's assume the initial activity of the sample to be x dps.

Using the formula for radioactive decay,

Activity = Initial activity x (1/2)^(time/ half-life)

where half-life is the time taken for the activity to reduce to half its initial value.

Calculating the half-life:

Activity after 300 days = Initial activity x (1/2)^(300/half-life)

5000 = x (1/2)^(300/half-life)

Similarly,

Activity after 450 days = Initial activity x (1/2)^(450/half-life)

2500 = x (1/2)^(450/half-life)

Dividing the two equations,

5000/2500 = (1/2)^(300/half-life) / (1/2)^(450/half-life)

2 = (1/2)^(150/half-life)

Taking logarithm on both sides,

log 2 = (150/half-life) log (1/2)

log 2 = (-150/half-life)

half-life = 150 log 2

Substituting the value of half-life in the first equation,

5000 = x (1/2)^(300/(150 log 2))

Solving for x,

x = 20000 dps

Hence, the initial activity of the sample was 20000 dps.
Free Test
Community Answer
After 300 days, the activity of a radioactive sample is 5000 dps (disi...
Attention NEET Students!
To make sure you are not studying endlessly, EduRev has designed NEET study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in NEET.
Explore Courses for NEET exam

Top Courses for NEET

After 300 days, the activity of a radioactive sample is 5000 dps (disintegrations per sec). The activity becomes 2500 dps after another 150 days. The initial activity of the sample in dps isa)20,000 b)10,000c)7,000 d)25,000Correct answer is option 'A'. Can you explain this answer?
Question Description
After 300 days, the activity of a radioactive sample is 5000 dps (disintegrations per sec). The activity becomes 2500 dps after another 150 days. The initial activity of the sample in dps isa)20,000 b)10,000c)7,000 d)25,000Correct answer is option 'A'. Can you explain this answer? for NEET 2024 is part of NEET preparation. The Question and answers have been prepared according to the NEET exam syllabus. Information about After 300 days, the activity of a radioactive sample is 5000 dps (disintegrations per sec). The activity becomes 2500 dps after another 150 days. The initial activity of the sample in dps isa)20,000 b)10,000c)7,000 d)25,000Correct answer is option 'A'. Can you explain this answer? covers all topics & solutions for NEET 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for After 300 days, the activity of a radioactive sample is 5000 dps (disintegrations per sec). The activity becomes 2500 dps after another 150 days. The initial activity of the sample in dps isa)20,000 b)10,000c)7,000 d)25,000Correct answer is option 'A'. Can you explain this answer?.
Solutions for After 300 days, the activity of a radioactive sample is 5000 dps (disintegrations per sec). The activity becomes 2500 dps after another 150 days. The initial activity of the sample in dps isa)20,000 b)10,000c)7,000 d)25,000Correct answer is option 'A'. Can you explain this answer? in English & in Hindi are available as part of our courses for NEET. Download more important topics, notes, lectures and mock test series for NEET Exam by signing up for free.
Here you can find the meaning of After 300 days, the activity of a radioactive sample is 5000 dps (disintegrations per sec). The activity becomes 2500 dps after another 150 days. The initial activity of the sample in dps isa)20,000 b)10,000c)7,000 d)25,000Correct answer is option 'A'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of After 300 days, the activity of a radioactive sample is 5000 dps (disintegrations per sec). The activity becomes 2500 dps after another 150 days. The initial activity of the sample in dps isa)20,000 b)10,000c)7,000 d)25,000Correct answer is option 'A'. Can you explain this answer?, a detailed solution for After 300 days, the activity of a radioactive sample is 5000 dps (disintegrations per sec). The activity becomes 2500 dps after another 150 days. The initial activity of the sample in dps isa)20,000 b)10,000c)7,000 d)25,000Correct answer is option 'A'. Can you explain this answer? has been provided alongside types of After 300 days, the activity of a radioactive sample is 5000 dps (disintegrations per sec). The activity becomes 2500 dps after another 150 days. The initial activity of the sample in dps isa)20,000 b)10,000c)7,000 d)25,000Correct answer is option 'A'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice After 300 days, the activity of a radioactive sample is 5000 dps (disintegrations per sec). The activity becomes 2500 dps after another 150 days. The initial activity of the sample in dps isa)20,000 b)10,000c)7,000 d)25,000Correct answer is option 'A'. Can you explain this answer? tests, examples and also practice NEET tests.
Explore Courses for NEET exam

Top Courses for NEET

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev