Answer:
Geocentric model of the universe
Explanation:
In the geocentric model of the universe, the earth is the center of the universe. This theory was later replaced by the heliocentric model which places the sun as the center.
This belief was propagated by the ancient Greeks. The geocentric model of the universe was proposed by Ptolemy.
The model suggests that other planetary bodies orbits the earth.
Protons are positive, and neutrons are negative, electrons are neutral. I’m not sure about the rest but I hope that helps for now
The formula for force exerted on/by a spring is
F = k*e where k is the spring constant and x is the distance stretched from
unstrained position. This should allow you to find what you need.
Using F = k x e,
where k is the spring constant,
and e is the extension,
The F is her weight = 45 X 0.80
= 36 N
Answer:
Thus the time taken is calculated as 387.69 years
Solution:
As per the question:
Half life of
= 28.5 yrs
Now,
To calculate the time, t in which the 99.99% of the release in the reactor:
By using the formula:

where
N = No. of nuclei left after time t
= No. of nuclei initially started with

(Since, 100% - 99.99% = 0.01%)
Thus

Taking log on both the sides:


t = 387.69 yrs
Answer:
Explanation:
Check attachment for solution