Answer:
t = 3.414 s
s = 23.3 m
Explanation:
Let t be the total time of motion
Let s be the total distance of motion
s - s/2 = ½at² - ½a(t - 1²) = ½a(t² - (t - 1)²)
s/2 = ½a(t² - (t² - 2t + 1)) = ½a(t² - t² + 2t - 1)
s = a(2t - 1)
s = 4(2t - 1)
s = 8t - 4
8t - 4 = ½4t²
8t - 4 = 2t²
0 = 2t² - 8t + 4
0 = t² - 4t + 2
t = (4 ±√(4² - 4(1)(2))) / 2 = (4 ± √8)/2 = 2 ± √2
t = 3.414 s
or
t = 0.5857... s which we ignore because it does not have a full last second.
s = ½(4)3.414² = 23.3137... 23.3 m
Answer:
Slope = 0.50.
Explanation:
Below is an attachment containing the solution to the question.
Answer:
Electrons.
Explanation:
Electricity was discovered before the discovery of electrons by J.J Thompson in 1896. Before the electron, it was thought that it is the positive ions that move through the wire and carry current—that's why today the conventional current represents the flow of positive charges.
After J.J Thompson's discovery of the electrons, it was realized that it is the electrons that actually carry the current through the conductor. But changing the direction of the conventional current didn't seem appropriate, and that's why the convention continues to be used to this day—reminding us that once it were the positive ions that were thought to carry the current.
The Doppler effect says that the observed wavelength is shortened
when the source is approaching the observer, and lengthened when
the source is receding from the observer.
All we can say about the police car and its siren is that the sound/color
has a shorter wavelength as it approaches us, and a longer wavelength
as it recedes.
Any of these pairs of answers would say that:
A -- A
C -- A
D -- A
or
D -- D
For each of these pairs, the second wavelength is longer than the first one.
(We don't know which pair is the actual one, because we don't know the actual color of the police car.)
