<span>The rate of conductivity is different among different substances, like aluminum, steel, and copper. Aluminum conducts heat the fastest at 910 j/kgaac. Steel is next and conducts heat at 450 j/kgaac. Copper conducts heat the slowest at 390 j/kgaac.</span>
Nuclear decay formula is N(t)=N₀*2^-(t/T), where N(t) is the amount of nuclear material in some moment t, N₀ is the original amount of nuclear material, t is time and T is the half life of the material, in this case carbon 14. In our case N(t)=12.5% of N₀ or N(t)=0.125*N₀, T=5730 years and we need to solve for t:
0.125*N₀=N₀*2^-(t/T), N₀ cancels out and we get:
0.125=2^-(t/T),
ln(0.125)=ln(2^-(t/T))
ln(0.125)=-(t/T)*ln(2), we divide by ln(2),
ln(0.125)/ln(2)=-t/T, multiply by T,
{ln(0.125)/ln(2)}*T=-t, divide by (-1) and plug in T=5730 years,
{ln(0.125)/[-ln(2)]}*5730=t
t=3*5730=17190 years.
The bone is t= 17190 years old.
Answer:
Explanation:
An object falling loses gravitational potential energy and gains kinetic energy. The gravity potential is the gravitational potential energy per unit mass. This energy comes from the gravitational potential energy released when the water falls. ... At 0, all the energy is in gravitational potential energy.
I think the answer would be c
Answer:
15.75 m
Explanation:
First, let's look at the top brick by itself. In order for it not to tip over the bottom brick, its center of gravity must be right at the edge of the bottom brick. So the edge of the top brick must be 10.5 m from the edge of the bottom brick.
Now let's look at both bricks as a combined mass. We know the total length of this combined brick is 10.5 m + 21 m = 31.5 m. And we know that for it to not tip over the edge of the surface, its center of gravity must be at the edge. So the edge of the combined brick must be 31.5 m / 2 = 15.75 m from the edge of the surface.
