1. Amperes, is the SI unit (also a fundamental unit) responsible for current.
2. 
Δq over Δt technically
Rearrange for Δq
I x Δt = Δq
1.5mA x 5 = Δq
Δq = 0.0075
Divide this by the fundamental charge "e"
Electrons: 0.0075 / 1.60 x 10^-19
Electrons: 4.6875 x 10^16 or 4.7 x 10^16
3. So we know that the end resistances will be equal so:
ρ = RA/L
ρL = RA
ρL/A = R
Now we can set up two equations one for the resistance of the aluminum bar and one for the copper: Where 1 represents aluminum and 2 represents copper
We are looking for L2 so we can isolate using algebra to get:
If you fill in those values you get 0.0205
or 2.05 cm
Answer:
When uranium is mined, it consists of approximately 99.3% uranium-238 (U238), 0.7% uranium-235 (U235), and < 0.01% uranium-234 (U234). These are the different uranium isotopes. Isotopes of uranium contain 92 protons in the atom's center or nucleus. (The number of protons in the nucleus is what makes the atoms "uranium.") The U238 atoms contain 146 neutrons, the U235 atoms contain 143 neutrons, and the U234 atoms contain only 142 neutrons. The total number of protons plus neutrons gives the atomic mass of each isotope — that is 238, 235, or 234, respectively. On an atomic level, the size and weight of these isotopes are slightly different. This implies that with the right equipment and under the right conditions, the isotopes can be separated.
Explanation:
Refraction is the change in direction of a wave.
Diffraction is the bending of a wave around a barrier.
Answer:
4. Electrons move from higher energy states to lower energy states.
Explanation:
When electrons fall from a higher (excited) energy state to a lower energy state, it loses/gives out energy.
This energy is given out by the emission of photons (quanta of light) by the electron.
Answer:
1/8
Explanation:
17,100 years is 3 times the half-life of 5,700 years. After each half-life, half remains, so the amount remaining after 3 half-lives is ...
(1/2)(1/2)(1/2) = 1/8
1/8 of the sample remains after 17,100 years.
