bidyogammes
Surface Areas of Prisms Cube: 6 x breadth x Height Triangular Prism: (Breadth x Height) + (3 x Length x Breadth) Square Pyramid: (2 x Breadth x Height) + (Breadth x Breadth) Cylinder: (2 x Pi x radius x Length) + (2 x Pi x Radius x Radius) Cone: (Pi x Radius x Height) + (Pi x Radius x Radius) Sphere: Pi x Radius x Radius x 4 By Austin from a Christian school in Belrose, NSW
Use the formula: 2X3.14Xr2Xh + 2X3.14XrXh it may be confusing, because it is long 2 times pi time radius squared times height plus 2 times pi times radius times height.
For a pipe of uniform radius and thickness, I believe the total surface area would be the Outside surface + Inside surface+ 2 times the surface of the ends. The inside radius(rinner), pipe thickness (t), and pipe length (L) are given.So you only need to find the outside radius (Rout) and then all areas can be calculated.The outside radius should be Rout=rinner +t. And note the perimeter of a circle is 2*pi*Radius and area of an annular region (in this case the ends of the pipe) is A= pi*(Rout2 - rinner2)For the outer pipe surface: Aout=2*pi*(Rout)*LFor the inner pipe surface: Ainner=2*pi*(rinner)*LFor each pipe end: Aend= pi*(Rout2 - rinner2)So the total surface area of the pipe would be: Aout+ Ainner+2* AendOr: Atotal =2*pi*(Rout)*L+2*pi*(rinner)*L+ 2*pi*(Rout2-rinner2)= pi*[ 2*L*(Rout + rinner)]+(Rout2 - rinner2)= 2*pi*[ L*( rinner +t + rinner)]+(( rinner +t )2 - rinner2)]=2*pi*(t+L)(t+2*rinner)Hopefully that is correct and helps.
the surface area
If the lengths are in the ratio 3:5, then the surface areas are in the ratio 9:25.
The energy is radiated equally in all directions into a sphere with a radius of 150 million kilometres, which has a surface area. On that sphere sits the Earth with a radius of 6378 kilometres, which has a circular cross-section area which intercepts part of the total energy. The ratio of the two areas answers the question.
The surface area of a sphere is proportional to the square of its radius. If the scale factor between the two spheres is 13, the ratio of their surface areas will be (13^2 = 169). Therefore, the surface area of the larger sphere is (16 , \text{ft}^2 \times 169 = 2704 , \text{ft}^2).
The formula for the surface area of a sphere is 4πr2. The formula for the volume of a sphere is 4/3πr3.
A surface area of 804.2 cm2
0- a sphere is a 3D surface with continuous curvature ( it does not have to have any flat areas)
Not necessarily. Having the same volume does not mean having the same surface area. As an example, if you were to take a sphere with volume 4/3*pi*r^3, and a suface area of 4*pi*r^2, and compare it to a cube with sides 4/3, pi, and 4^3, you would find that they had a different surface area, but the same volume. Let the radius of the sphere be 2, that is r = 2. In this case the surface are of the sphere is about 50, and the surface are of the cube is about 80. So a sphere and a cube, both with a volume of about 33.51 (4/3 * pi * 8), have different surface areas.
( The volume of a sphere is (4/3)(pi)r3 ). The short answer: because of calculus. The long answer: This can be seen by using calculus to derive the volume of a sphere from the formula from it's surface area. To do this, we imagine that the sphere is full of infinity thin spheres inside it (all centered at the big sphere's center), and add up the surface areas of all the spheres inside. The formula for the surface area of a sphere is 4(pi)r2. Let's call R the radius of the big sphere we want to find the volume of. To find the volume of this sphere, we add up the surface areas of all the spheres whose radii range from 0 to R. This gives the following formula (where r is the radius of each little sphere): 0R∫ 4(pi)r2dr The 4 and pi can be factored out giving: 4(pi) (0R∫r2dr) Integrating gives: 4(pi) [r3/3]0R This is where the three comes from. Finishing the evaluation of the integral gives: 4(pi)(R3/3 - 03/3) = 4(pi)(R3/3) Which can be rewritten as (4/3)pi(R3) which is the formula for the volume of a sphere.
Surface Areas of Prisms Cube: 6 x breadth x Height Triangular Prism: (Breadth x Height) + (3 x Length x Breadth) Square Pyramid: (2 x Breadth x Height) + (Breadth x Breadth) Cylinder: (2 x Pi x radius x Length) + (2 x Pi x Radius x Radius) Cone: (Pi x Radius x Height) + (Pi x Radius x Radius) Sphere: Pi x Radius x Radius x 4 By Austin from a Christian school in Belrose
Surface Areas of Prisms Cube: 6 x breadth x Height Triangular Prism: (Breadth x Height) + (3 x Length x Breadth) Square Pyramid: (2 x Breadth x Height) + (Breadth x Breadth) Cylinder: (2 x Pi x radius x Length) + (2 x Pi x Radius x Radius) Cone: (Pi x Radius x Height) + (Pi x Radius x Radius) Sphere: Pi x Radius x Radius x 4 By Austin from a Christian school in Belrose
Surface Areas of Prisms Cube: 6 x breadth x Height Triangular Prism: (Breadth x Height) + (3 x Length x Breadth) Square Pyramid: (2 x Breadth x Height) + (Breadth x Breadth) Cylinder: (2 x Pi x radius x Length) + (2 x Pi x Radius x Radius) Cone: (Pi x Radius x Height) + (Pi x Radius x Radius) Sphere: Pi x Radius x Radius x 4 By Austin from a Christian school in Belrose, NSW
No. The curved surface of the cylinders would be the same but the areas of the circular discs at the two ends of the cylinder would be unchanged in the first case but quartered in the second.
The ratio of the surface areas is (earth's radius/moon's radius)^2 where the radii are in the same units.This gives the answer as 13.40, approx.And, incidentally, the word is radius, not raduis!