ACTION Funicular Sometimes a cliff face is just too steep to climb easily So engineers developed a special kind of railway to take passengers up and down It’s called a funicular A funicular is a kind of cable railway The cable is attached to two cars that run on rails and to a pulley The cars look a little like trolleys The cable moves the cars up and down the steep slope As one goes up the other one going down counterbalances it This means that its weight as it is lowered is equal to the weight of the vehicle going up It balances its weight This makes the vehicle going up easier to pull At the top of the slope the cable runs through a pulley system The pulley system is usually turned by an electric motor Special wheels guide the cable from the pulley mechanism to the cars and back again 4What is the name of the force that pulls on the funicular
5 Although funiculars usually use electric power to move the cars up a steep slope gravity is also helping Gravity is a force that pulls on things It is the pulling power of Earth that holds everything on or close to the planet and stops things from jumping off and floating away including you ANSWER GRAVITY The pull of gravity between two things depends on the distance between them It also depends on how much stuff called mass they are made up of The greater their mass the greater the force of gravity that will pull on them The amount of gravity pulling on something is called its weight We measure weight in units called newtons So it’s the force of gravity that pulls the downward travelling car down And it’s the same force that helps pull the other car up
The hovercraft skims smoothly just above the surface of the water It travels on a cushion of air such that it moves faster faster than vessels that have to push their way through the waves Hovercrafts are used for fast ferry services but they can travel over land as well so they are useful in crossing swampy or rough ground As the hovercraft moves forward air is drawn in through fans on the top of the craft A rubber skirt around the edge and about 18 inches deep holds in the air like a cushion ACTION Hovercraft 6What force raises the hovercraft above the ground
ANSWER AIR PRESSURE You can’t see it but you can feel it when the wind blows It’s air There’s air all around us It’s the atmosphere that surrounds our planet and its around 600 miles thick Because the atmosphere is made up of different gases it has weight and it takes up space The weight of the atmosphere causes it to press down on us This pressing down is called air pressure You don’t normally feel the air pressure pressing on you because there’s an equal amount inside your body pressing outwards to balance it lower air pressure higher air pressure sea level 7 A hovercraft creates its own extra air pressure Air can’t escape through the skirts so it forces the craft up allowing it to skim over the waves The bottom of the skirt can move up and down and follow the movement of the waves so this helps keep the hovercraft steady
