A. Angular momentum is always conserved would be the correct answer.
This is because like linear momentum (mvmv), angular momentum (r×mvr×mv) is a conserved quantity, where rr is the vector from the center of rotation. For a skater holding a static pose, for each particle making up her body, the contribution in magnitude to the total angular momentum is given by mirivimirivi. Thus bringing in her arms reduces riri for those particles. In order to conserve angular momentum, there is then an increase in the angular velocity.
hope this helps!
Wind<span> power
holds great promise for the united states because of the great wind power (capacity),
and experts believe wind energy could meet as much as 20 percent of the
nation’s energy needs
. Texas is the state with most wind capacity. On the second place is Iowa and oh the third place Oklahoma. The wind farms produce clean energy that does not harm the environment.</span>
Answer:
Explanation:
from snells law we have following relation
is refractive index of air
n' - refractive index of air below
i is angle of incidence = 90 - 1.30 = 88.70^o
r is refraction angle
plugging all value in above formula
Answer:
4.5 m/s
Explanation:
The rock must barely clear the shelf below, this means that the horizontal distance covered must be
while the vertical distance covered must be
The rock is thrown horizontally with velocity 
, so we can rewrite the horizontal distance as
where t is the time of flight. Re-arranging the equation,
(1)
The vertical distance covered instead is
where we omit the term 
since the initial vertical velocity is zero. From this equation,
(2)
Equating (1) and (2), we can solve the equation to find :
Answer:
d
Explanation:
you have to divide by the square root and then use the factorial to multiply
