Voting, running, speaking in front of government
Answer:
F. 0J
Explanation:
At the objects highest point in the trajectory the KE = 0 since this trajectory is completely vertical with no x-component but its PE would be greatest at this point.
KE = (1/2)mv²
KE = 0; because velocity equals 0
PE = m*g*h
PE = 1kg*(9.81m/s^2)*10m
PE = 98.1J
Answer:
11460 years
Explanation:
Let N₀ be the initial amount of carbon present. After one half-life, its value is N₀/2, after two half-lives, it is N₀/4 = N₀/2². After n nalf-lives, it is N = N₀/2ⁿ.
Now, if the value of carbon-14 drops to a quarter of its initial value, then N = N₀/4.
So, N₀/4 = N₀/2ⁿ
1/4 = 1/2ⁿ
1/2² = 1/2ⁿ
Comparing the exponents, n = 2.
So the value of carbon-14 present drops to a quarter of its initial value in 2 half-lives.
Since one-half life equals 5730 years, then two-half-lives is 2 × 5730 years = 11460 years
So, it takes carbon-14 11460 years for the number of nuclei to drop to a quarter of its initial value.