Answer:
The star-sphere discovered by the Greeks and other ancient civilizations which shows the physical location in space of the nearby stars.
Explanation:
The celestial sphere is an ideal sphere, without defined radius, concentric with the terrestrial globe, in which the stars apparently move. Some ancient civilizations such as the Greeks assumed that the stars were attached to a celestial sphere, which revolves around the earth, while our planet is always immobile.
Answer:
As follows,
Explanation:
KE=1/2mv^2
In 1st question,
KE=1/2mv^2=1/2*0.05*12=0.3 J [50g=0.05 kg]
In 2nd question,
KE=1/2mv^2
6.8=1/2*0.046*v^2
v=sqrt(6.8/0.023)
v=17.19
In 3rd question,
KE=1/2mv^2
63/392=m
m=0.16kg=160g
For 4th,
a.
1st case,
KE=1/2mv^2=1/2*28*2.4^2=80.64
2nd case,
KE=1/2mv^2=1/2*28*3.7^2=191.66
Change in KE=191.66-80.64=11.02
b.Speed/velocity gained
Answer:
container of hydrogen gas has a volume of 2.3m³. What is the mass of hydrogen
Answer:
64.5
Explanation:
(m1 + m2) v initial = (m1 * v1 final) + (m2 * v2 final)
(92 + 8)(-7) = (92 x 2) + (8 x v2 final)
(100)(-7) = (184) + (8 x v2 final)
-700 = (184) + (8 x v2 final)
-516 = (8 x v2 final)
-516/8 = v2 final
-64.5 = v2 final
Explanation:
The object is moving along the parabola y = x² and is at the point (√2, 2). Because the object is changing directions, it has a centripetal acceleration towards the center of the circle of curvature.
First, we need to find the radius of curvature. This is given by the equation:
R = [1 + (y')²]^(³/₂) / |y"|
y' = 2x and y" = 2:
R = [1 + (2x)²]^(³/₂) / |2|
R = (1 + 4x²)^(³/₂) / 2
At x = √2:
R = (1 + 4(√2)²)^(³/₂) / 2
R = (9)^(³/₂) / 2
R = 27 / 2
R = 13.5
So the centripetal force is:
F = m v² / r
F = m (5)² / 13.5
F = 1.85 m
