Answer:
B. the stars to come back to the same positions in the sky.
Explanation:
In fact, the solar day is equivalent to more than a rotation, because when the point has turned completely, it is not, as it should, in the same position with respect to the Sun.
The reason for this is that while performing the rotation, the Earth simultaneously moved following its orbit around the Sun.
When the reference point completed its rotation, the Earth already moved almost 2,500,000 km., So that to see the Sun again it will be necessary to turn a little more.
Solar day is more than a rotation. The sidereal or sidereal day, commonly used by astronomers, is also based on the rotation of the Earth; but in this case a distant star is taken as a reference (sidereal comes from the Latin sidus which means "star").
It’s true
an atom as a whole is electrically neutral
A. The formula for mean free time is:
t = V/(4π√2 r²vN)
where
N = 1×10¹⁶ molecules (per m³)
V = 1 m³
r = 111×10⁻⁷m (atomic radius of silicon)
Let's solve for v first:
v = √(3RT/M) = √(3(8.314 m³·Pa/mol·K)(25 + 273 K)/28.1 g/mol Si)
v = 16.26 m/s
t = (1 m³)/(4π√2 (111×10⁻⁷m)²(16.26 m/s)(1×10¹⁶ molecules))
<em>t = 2.81×10⁻9 s</em>
<em>Pure silicon has a high resistivity relative to copper because copper is a conductor, while silicon is a semi-conductor. </em>
Answer: 14.1 m/s
Explanation:
We can solve this with the Conservation of Linear Momentum principle, which states the initial momentum 
(before the elastic collision) must be equal to the final momentum 
(after the elastic collision):
(1)
Being:
Where:
is the combined mass of Tubby and Libby with the car
is the velocity of Tubby and Libby with the car before the collision
is the combined mass of Flubby with its car
is the velocity of Flubby with the car before the collision
is the velocity of Tubby and Libby with the car after the collision
is the velocity of Flubby with the car after the collision
So, we have the following:
(2)
Finding :
(3)
(4)
Finally:
Let's just assume that you throw the ball with an initial speed of 2 m/s instead of dropping it like free falling.
a=9.81 m/s^2
Vi= 2 m/s
t= 3 x
we use the formula
d = (Vi)(t) + (1/2)(a)(t)^2
d= (2)(3) + (1/2)(9.81)(9)
d=50.145 m
