A: Geometry is too bad to understand the formula, chord length 120 meters, chord center to arc top 40 meters, find arc length, urgent B: Given the diameter of the ball 83 meters, find a quarter of the surface area of the ball

A: Geometry is too bad to understand the formula, chord length 120 meters, chord center to arc top 40 meters, find arc length, urgent B: Given the diameter of the ball 83 meters, find a quarter of the surface area of the ball

Circle radius r, chord length 2A = 120, chord height h = 40
R^2-a^2=(R-H)^2,R=65
The center angle of the circle is about 135 degrees, arc length = 135 / 180 * π r = 153
Formula of sphere surface area: S = 4 π * R ^ 2, (R is radius)
R=83/2=41.5
1 / 4 sphere surface area = π * R ^ 2 = π * 41.5 ^ 2 = 5410 (about)
^2 is the square

Geometry is too bad to understand the formula, chord length 11.3 meters, chord center to arc top 2 meters, find arc length

Chord length L = 11.3m, chord center to arc top H = 2m
The radius of arc is r, and the center angle of arc is a
R^2=(R-H)^2+(L/2)^2
R^2=R^2-2*R*H+H^2+L^2/4
2*R*H=H^2+L^2/4
R=H/2+L^2/(8*H)
=2/2+11.3^2/(8*1.5)
=11.64m
A=2*ARC SIN((L/2)/R)
=2*ARC SIN((11.3/2)/11.64)
=. degree
=. radian
C = a * r =. * 11.64 =. M
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Cut a sector with a radius of 10 cm from the paper and make a cone. The diameter of the bottom of the cone is 16 cm. Calculate the volume of the cone

According to Pythagorean theorem, height h = 6, bottom area s = 200.96 or 64 π, Volume V = 1 / 3, HS = 128 π or 401.92
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Cut a sector with a radius of 10 cm from the paper, make a cone with a height of 8 cm, and find out the volume of the cone

r²=10²-8²
R = 6 (- 6 rounding off)
V = (1 / 3) × 3.14 × 6 & # 178; × 8 = 301.44 cm3

Cut a sector with a radius of 10 cm and 216 ° from the paper and make a cone with a height of 8 cm. What is the volume of this cone in cubic cm?

Conic radius = 10 × (216 °△ 360 °) = 6cm
Volume = 1 / 3 × bottom area × height = 1 / 3 × 3.14 × 6 & # 178; × 8 = 301.44 cm3
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The diameter of the bottom of a cone is 8 cm and the height is 12 cm. What is the volume of the cone?

The diameter of the bottom surface is 8 cm and the radius is 4 cm
The volume of cone = 1 / 3 × 3.14 × 4 × 4 × 12 = 200.96 cubic centimeter

The bottom diameter of a cone is 8 cm and its height is 1 / 4 of the diameter
What's one-third

The diameter of the bottom of a cone is 8 cm, and its height is 1 / 4 of the diameter
8 × 5 / 4 = 10 (CM)
According to the volume formula of cone, we can get: 1 / 3 × (8 △ 2) × (8 △ 2) × 3.14 × 10 ≈ 167.47
(one third is one third)

The volume of a cone is 5.024 cubic centimeters, the diameter of its bottom is 4 centimeters, and how high is the cone?

Height of cone = volume of cone divided by bottom area x3
3.14X2X2=12.56
5.024÷12.56X3=1.2cm
A: the height of the cone is 1.2cm

The diameter of the bottom of a cone is 16 cm and the height is 18 cm. What is the volume of this cone

Cone volume: V cone = bottom area (bottom area = 3.14 × R × R, R is radius) × height × 1 / 3 (1 / 3 = 1 / 3)
So the answer is 3.14 × 8 × 8 × 18 × 1 / 3

The bottom radius of a cone is 9 cm, and its height is 2 / 3 of its diameter. What is the volume of the cone?

Hello
Bottom area = 3.14 × 9 & # 178; = 254.34 (cm2)
Height = 9 × 2 × 2 / 3 = 12 (CM)
Cone volume = 1 / 3 × 254.34 × 12 = 1017.36 (cm3)