<h3><u>Answer;</u></h3>
Carbon-14 levels in a sample are undetectable after approximately 9 half lives
<h3><u>Explanation;</u></h3>
- <em><u>The half life of Carbon-14 is 5,730 years . Half life is the time taken by a radioactive material to decay by half of its original mass. Therefore, it would take a time of 5730 years for a sample of 100 g of carbon-14 to decay to 50 grams</u></em>
- <em><u>A period of 50,000 years, is equivalent to; </u></em>
<em><u> 50,000÷5,730 </u></em>
<em><u>= 8.73 half lives</u></em>
<em>Which is approximately equal to 9 half lives.</em>
- Therefore, if the age of an object older than 50,000 years cannot be determined by radiocarbon dating, then <em><u>Carbon-14 levels in a sample are undetectable after approximately 9 half lives</u></em>.
Answer:
doing her homework/finding time to do important things
2.25 m/s² of acceleration is required to increase the speed of a car from 26 mi/h to 51 mi/h in 5 seconds.
To find the answer, we need to know about the acceleration.
<h3>What is acceleration?</h3>
- Acceleration is given as the ratio of velocity to time.
- Mathematically, acceleration= velocity/time.
<h3>What is the acceleration required to increase the speed of a car from 26 mi/h to 51 mi/h in 5 seconds?</h3>
- Here change in velocity of the car is 51-26= 25 mi/h.
- As 1 mi/h = 0.45 m/s. So 25mi/h = 11.25 m/s.
- Acceleration= (11.25m/s)/5s = 2.25 m/s².
Thus, we can conclude that the constant acceleration is 2.25 m/s².
Learn more about the acceleration here:
brainly.com/question/460763
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Answer:
f = 1 / [ 2*pi*R*C*Sqrt(2*N)
Explanation:
f = 1 / [ 2*pi*R*C*Sqrt(2*N) is the formula. Sorry I answered in English.
$0.60
90 mins is 1.5 hrs
5 kW × 1.5 = 7.5 kWh
7.5 kWh × $0.08 = $0.60
