Answer: B. meteorites, UV rays
The earth's atmosphere plays an important role in shielding the space rocks and meteorites enters inside the earth due to collision with the celestial body. Due to high heat and pressure in the mesospheric layer of the atmosphere these meteorites burned up before reaching the biosphere or hydrosphere system of the earth. The UV rays are protected from entering into the earth atmosphere by the ozone layer present in the stratosphere of the atmosphere. Both meteorites and UV rays can negatively effect the human population. Therefore, the atmosphere is an agent which provides protection against them.
<span>Nuclear energy can be used to power all of
the above choices. Nuclear power plants produce radioactive waste that must be
stored properly. It is very impossible for a nuclear power plant to have no
waste at all since lots of chemicals are used to create the process as it gives
energy to other machines, weapons such as bombs and powering submarines. Radioactive waste can not be released into
local water supplies since the wastes are very radioactive and may cause
mutation to the fishes and bioaccumulation which will affect humans as well. It
will also cause air pollution if the chemicals are not stored properly.</span>
Answer:
a. Capacitance
b. Charge on the plates
e. Energy stored in the capacitor
Explanation:
Let A be the area of the capacitor plate
The capacitance of a capacitor is given as;
where;
V is the potential difference between the plates
The charge on the plates is given as;
The energy stored in the capacitor is given as;
Thus, the physical variables listed that will change include;
a. Capacitance
b. Charge on the plates
e. Energy stored in the capacitor
Answer:
21.3 V, 1.2 A
Explanation:
1.
These resistors are in series, so the net resistance is:
R = R₁ + R₂ + R₃
R = 20 + 30 + 45
R = 95
So the current is:
V = IR
45 = I (95)
I = 9/19
So the voltage drop across R₃ is:
V = IR
V = (9/19) (45)
V ≈ 21.3 V
2.
First, we need to find the equivalent resistance of R₂ and R₃, which are in parallel:
1/R₂₃ = 1/R₂ + 1/R₃
1/R₂₃ = 1/10 + 1/10
R₂₃ = 5
Now we find the overall resistance by adding the resistors in series:
R = R₁ + R₂₃ + R₄
R = 10 + 5 + 10
R = 25
So the current through R₁ is:
V = IR
30 = I (25)
I = 1.2 A
Answer:
C. 3.2 x 10^8 Ω•m
Explanation:
An insulator is a material that resists the flow of electricity.
In the given data the material with the highest resistivity is the best insulator
3.2 x 10^8 Ω•m
