Answer:
The concentration of benzene in this contaminated lake would be 653549ng/L.
Explanation:
The concentration C of a contaminant over a body of water of volume V can be obtained as:
C=Mass contaminant / V
In this case, the volume of the body of water:
The mass of the contaminant (Benzene):
Therefore:
Answer:
150 W
Explanation:
Power is energy per unit time. The power generated by the engine is ...
(3000 J)/(20 s) = 150 J/s = 150 W
The engine generated 150 watts.
Question:
In a typical transmission line, the current I is very small and the voltage V is very large. A unit length of the line has resistance R.
For a power line that supplies power to 10 000 households, we can conclude that
a) IV < I²R
b) I²R = 0
c) IV = I²R
d) IV > I²R
e) I = V/R
Answer:
d) IV > I²R
Explanation:
In a typical transmission line, the current I is very small and the voltage V is very high as to minimize the I²R losses in the transmission line.
The power delivered to households is given by
P = IV
The losses in the transmission line are given by
Ploss = I²R
Therefore, the relation IV > I²R holds true, the power delivered to the consumers is always greater than the power lost in the transmission line.
Moreover, losses cannot be more than the power delivered. Losses cannot be zero since the transmission line has some resistance. The power delivered to the consumers is always greater than the power lost in the transmission.
Answer:
In the result of a earthquake, you should direct people into areas that are safe, such as places where the ground has not been broken up, and then tell people to get out of their cars and be careful. You should also have them carry any valuable items out of the car(if they have time), and then wait until the initial shocks and aftershocks are over, and then tell them to get back into their cars and then drive carefully and safely.
