Deprecated: Methods with the same name as their class will not be constructors in a future version of PHP; plgContentJComments has a deprecated constructor in /var/www/astarmathsandphysics/plugins/content/jcomments/jcomments.php on line 25 Call Stack: 0.0000 360576 1. {main}() /var/www/astarmathsandphysics/index.php:0 0.0520 1210632 2. Joomla\CMS\Application\SiteApplication->execute() /var/www/astarmathsandphysics/index.php:49 0.0520 1210632 3. Joomla\CMS\Application\SiteApplication->doExecute() /var/www/astarmathsandphysics/libraries/src/Application/CMSApplication.php:267 0.1285 4131200 4. Joomla\CMS\Application\SiteApplication->dispatch() /var/www/astarmathsandphysics/libraries/src/Application/SiteApplication.php:233 0.1299 4158544 5. Joomla\CMS\Component\ComponentHelper::renderComponent() /var/www/astarmathsandphysics/libraries/src/Application/SiteApplication.php:194 0.1306 4176256 6. Joomla\CMS\Component\ComponentHelper::executeComponent() /var/www/astarmathsandphysics/libraries/src/Component/ComponentHelper.php:356 0.1308 4206776 7. require_once('/var/www/astarmathsandphysics/components/com_content/content.php') /var/www/astarmathsandphysics/libraries/src/Component/ComponentHelper.php:381 0.1319 4229496 8. ContentController->execute() /var/www/astarmathsandphysics/components/com_content/content.php:42 0.1319 4229496 9. ContentController->display() /var/www/astarmathsandphysics/libraries/src/MVC/Controller/BaseController.php:710 0.1850 4907064 10. ContentController->display() /var/www/astarmathsandphysics/components/com_content/controller.php:113 0.1885 5099216 11. Joomla\CMS\Cache\Controller\ViewController->get() /var/www/astarmathsandphysics/libraries/src/MVC/Controller/BaseController.php:663 0.1890 5120144 12. ContentViewArticle->display() /var/www/astarmathsandphysics/libraries/src/Cache/Controller/ViewController.php:102 0.2005 5311416 13. Joomla\CMS\Plugin\PluginHelper::importPlugin() /var/www/astarmathsandphysics/components/com_content/views/article/view.html.php:189 0.2005 5311672 14. Joomla\CMS\Plugin\PluginHelper::import() /var/www/astarmathsandphysics/libraries/src/Plugin/PluginHelper.php:182

Nets and Surface Areas

To find the surface area of a solid shape, we should often first draw the net of the solid. This involves 'unfolding' the solid onto a flat surface and finding the areas of individual parts of the net, which are often simple shapes like rectangles, squares, triangles and circles.

To find the area of the cuboid below,

draw the net, with the length of each side, which looks like

The area is then easily calculated as shown below.

The total area is the sum of the individual areas:

To find the surface area of the cylinder below,

Draw the net, shown below.

The area of each circle is

The base of the curved surface, shown above as a rectangle, is equal to the circumference of the circle, so the area of the rectangle isand the total surface area is

To find the surface area of the right angled triangular prism below,

draw the net, shown below.

The area of each shape is shown below.

The total area is the sum of the individual area:

The net of a cone is a sector of a circle, representing the curved surface, plus a circle, representing the base. If the slant height is l and the radius of the base is r,

The curved surface area isand the area of the base isThe net is shown below.

The total area is

Add comment

Security code