Set this up as
10 = 40 (1/2)t/28
and solve for t in years.
10/40 = (1/2)t/28
log(0.25) = (t/28) log(0.5)
t = 28 log(0.25) / log(0.5) years = 56 years
Test the answer:
56 years = 2(28 years) = 2 half-lives, so the remaining amount should be 1/2 of 1/2 of the initial amount, i.e. 1/4 of the initial amount, and 10 mg = 1/4 of 40 mg.
Answer:
She is known as Bloody Mary because of the numbers of people who were executed for being Protestants. Mary burned nearly three hundred Protestants at the stake when they refused to give up their religion. -google
This is false, as the equator does not run north-south. The equators is the line that goes all around the planet in equal distance from the two poles: so it runs west-east.
It is true however that it runs roughly through the middle of the continent of Africa, but rather on the west-east axis.
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Answer:
A. 29.4 Joules
Explanation:
Given parameters:
Mass of the book = 1.5kg
Height of lift = 2m
Unknown:
Potential energy acquired = ?
Solution:
Potential energy is the energy due to the position of a body.
Mathematically;
Potential energy = mgh
m is the mass of the body
g is the acceleration due to gravity = 9.8m/s²
h is the height
Potential energy = 1.5 x 9.8 x 2
Potential energy = 29.4J