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makvit [3.9K]
3 years ago
11

Will mark brainliest! Please help!

Physics
1 answer:
djverab [1.8K]3 years ago
3 0

Answer:

30 seconds

Explanation:

A = A02^-(t/hl)

--> ln(A/A0) = -(t/hl)ln2

solving for hl,

hl = -t x ln2 /ln(A/A0)

= -(60 min)xln2/ln(50/200)

= 0.5 min or 30 seconds

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