It is C because less than one percent of water is fresh water
A metallic bond would be formed
New evidence may support the theory -> then nothing
New evidence conflicts with the theory => rework theory / create a new one
Answer:
1. The best definition of refraction is ____.
a. passing through a boundary
b. bouncing off a boundary
c. changing speed at a boundary
d. changing direction when crossing a boundary
Answer: D
Bouncing off a boundary (choice b) is reflection. Refraction involves passing through a boundary (choice a) and changing speed (choice c); however, a light ray can exhibit both of these behaviors without undergoing refraction (for instance, if it approaches the boundary along the normal). Refraction of light must involve a change in direction; the path must be altered at the boundary.
Answer:
w = 3.2 rev / min
Explanation:
For this exercise we will use the centrine acceleration equal to the acceleration of gravity
a = v² / r
Angular and linear variables are related.
v = w r
Let's replace
a = w² r = g
w = √ g / r
r = d / 2
r = 175/2 = 87.5 m
w = √( 9.8 / 87.5)
w = 0.3347 rad / s
Let's reduce to rotations per min
w = 0.3347 rad / s (1 rov / 2pi rad) (60 s / 1 min)
w = 3.2 rev / min
Suppose the space station rotates counterclockwise, we have two possibilities for the car
The first car turns counterclockwise (same direction of the station
=
r
[texwv_{c}[/tex] =
/ r
[texwv_{c}[/tex] = 25.0 / 87.5
[texwv_{c}[/tex] = 0.286 rad / s
When the two rotate in the same direction their angular speeds are subtracted
w total = w -[texwv_{c}[/tex]
w total = 0.3347 - 0.286
w total= 0.487 rad / s
The car goes in the opposite direction of the station the speeds add up
w = 0.3347 + 0.286
w = 0.62 rad / s
From this values we can see that the person feels a variation of the acceleration of gravity, feels that he has less weight when he goes in the same direction of the season and that his weight increases when he goes in the opposite direction to the season.