Answer:
In the human thoughts, there is possible and impossible. In God's world everything is possible. If you keep thinking this you'll never start to study. Just get up, open the book and start to study like you do. Believe in yourself!
Answer: 50%
Explanation: efficiency=power input/power output ×100
Eff.=300/600 ×100
Eff=½×100
Eff=50%
<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>.
If an object<span> has a net </span>force<span> acting on it, it will accelerate. The </span>object<span> will speed up, slow down or change direction. An </span>unbalanced force<span> (net </span>force<span>) acting on an </span>object<span>changes its speed and/or direction of motion. An </span>unbalanced force<span> is an unopposed</span>force<span> that causes a change in motion.
thus the car would get its speed, and or direction mixed up</span>
