IDNLearn.com offers a seamless experience for finding and sharing knowledge. Ask your questions and get detailed, reliable answers from our community of knowledgeable experts.
Sagot :
Answer:
e) 400 mg of a radioactive substance with a half-life of 8 hours after decaying for 8 hours
a) 800 mg of a radioactive substance with a half-life of 2 years after decaying for 4 years.
Explanation:
a) 800 mg of a radioactive substance with a half-life of 2 years after decaying for 4 years.
Number of half lives passed = Time elapsed/ half life
Number of half lives passed = 4 year/2 year
Number of half lives passed = 2
at time zero = 800 mg
At first half life = 800 mg/2 = 400 mg
At 2nd half life = 400 mg/2 = 200 mg
b) 1,000 mg of a radioactive substance with a half-life of 5 years after decaying for 20 years
Number of half lives passed = Time elapsed/ half life
Number of half lives passed = 20 year/ 5 year
Number of half lives passed = 4
at time zero = 1000 mg
At first half life = 1000 mg/2 = 500 mg
At 2nd half life = 500 mg/2 = 250 mg
At 3rd half life = 250 mg/2 = 125 mg
At 4th half life = 125 mg/2 = 62.5 mg
c) 300 mg of a radioactive substance with a half-life of 1 year after decaying for 1 year
Number of half lives passed = Time elapsed/ half life
Number of half lives passed = 1 year/ 1 year
Number of half lives passed = 1
at time zero = 300 mg
At first half life = 300 mg/2 = 150 mg
d) 600 mg of a radioactive substance with a half-life of 6 hours after decaying for 18 hours
Number of half lives passed = Time elapsed/ half life
Number of half lives passed = 18 hours / 6 hours
Number of half lives passed = 3
at time zero = 600 mg
At first half life = 600 mg/2 = 300mg
At 2nd half life = 300 mg/2 = 150 mg
At 3rd half life = 150 mg/2 = 75 mg
e) 400 mg of a radioactive substance with a half-life of 8 hours after decaying for 8 hours
Number of half lives passed = Time elapsed/ half life
Number of half lives passed = 8 hours / 8 hours
Number of half lives passed = 1
at time zero = 400 mg
At first half life = 400 mg/2 = 200 mg
Thank you for contributing to our discussion. Don't forget to check back for new answers. Keep asking, answering, and sharing useful information. Find precise solutions at IDNLearn.com. Thank you for trusting us with your queries, and we hope to see you again.