Answer:
the Earth-Sun distance.
Explanation:
To measure parallax the base line distance that we need to know is the Earth-Sun distance. This distance is called 1 astronomical unit. This distance is 1.496×10^8 Km. So, this base line distance is necessary for the second link parallax.
Answer: 2.73m/s
Explanation:
Potential energy of the water is turned into kinetic energy
mgd = mv^2/2
Where m = mass of water
g = acceleration due to gravity = 9.81m/s^2
d = depth of the water = 0.38m
v = velocity of leaking water
m × 9.81 × 0.38 = mv^2/
eliminate m on both sides and multiply through by 2
7.4456 = v^2
v = sqrt(7.4456)
v = 2.73m/s
If the echo (the reflected sound) reaches your ear less than about
0.1 second after the original sound, your brain doesn't separate them,
and you're not aware of the echo even though it's there.
If the echo comes from, say, a wall, 0.1 second means you'd have to be
about 17 meters away from the wall. If you're closer than that, then the
echo reaches you in less than 0.1 second and you're not aware of it.
A. 30 meters . . .
No. You hear that echo easily
B. you're standing within range of both sounds . . .
No. You hear that echo easily, if you're at least 17 meters from the wall.
C. less than 0.1 second later . . .
That's it. The echo is there but your brain doesn't know it.
D. 21.5 meters
No. You hear that echo easily.
Answer:
Mass and thus force depends on the reference frame chosen
Explanation:
This can be explained as Newton's law of gravity provides action which are instantaneous at a distance and involves the evaluation of all the quantities at present time or at the instant they occur.
If the body undergoes a change in its mass distribution there will be an immediate change in its gravitational force without any lag.
Now, if we talk about special relativity, it would be absurd to say that an information can travel faster than light. The effect is in synchronization with the cause in one reference frame where the effect occurs after the cause for some observer in some other reference frame.
In order to observe Newton's law of gravity all the observer's in different reference frames must observe the same phenomena which could only be possible if time were absolute and in special relativity, time is not absolute.
Therefore, Newton's law of gravity was inconsistent with the Einstein's Special Relativity.
Pathogens are microorganisms that cause infectious diseases. Bacteria and viruses are the main pathogens in the world today.
The major problem that pathogen cause in society is that they are the agents of infection and disease.
An infection results when a pathogen invades the body and begins growing within a host. A disease results when tissue function is impaired due to an infection.
Due to diseases, affected people can not work which negatively affects the economy, and the sick may end up dying causing a lot of grief, and robbing society of a father, a mother or child.
The government has to put money aside for health care which would otherwise have been used for other things to help the society.
