The current in a wire is defined as the amount of charge that passes a given point of the wire in a given time:
where Q is the charge and
is the time interval.
Since one electron has a charge of
, the total charge of
electrons is
And since the time interval is
, the current in the wire is
Hydroelectric energy is electricity generated by c. moving water.
You would figure this out by knowing what the root hydro is. Hydro means water. So then you could infer that Hydroelectric energy is from moving water.
They are both sites of new cell formation.
Answer:
answer a) 2
Explanation:
Assuming stationary state, following Fourier's law:
Q = A*k* dT/dL
where Q= heat flow , A= cross sectional area, dT/dL= temperature gradient along the bar
if the cross sectional area is doubled , then the gradient is the same ( since the heat sources do not change in temperature or position , and the length of the bar is the same). Since the gradient is same , the temperature is the same under stationary conditions , then we can assume k remains constant in the cross section.Therefore
Q₁= A₁*k* dT/dL
Q₂= A₂*k* dT/dL
dividing both equations
Q₂ / Q₁ = A₂/A₁ = 2
then the correct answer is a)
Note:
Since the cross sectional area is doubled, then heat loss to the surroundings will be
Q loss= h* A exposed * ΔT
then
Q loss₂ / Q loss ₁ = A exposed ₂/ A exposed ₁
for a circular cross section or a squared cross section
A exposed ₂/ A exposed ₁ = √2
then
Q loss₂ / Q loss ₁ = √2
therefore we did not take into account the increase in heat loss due to the increased in exposed area to the environment
From those choices, the best is the third one.
it relates to why the sun and almost everything else in the solar system spins in the same direction, and also why the abundance of various elements in the planets is so different from what it is in the sun.