This term in Science we have been studying gravity, air resistance, levers, air pressure, forces and friction. We have carried out lots of experiments. Here are some of them.
1. Levers – To show that the nearer the fulcrum is to the load; the easier it is to lift the load.
• A bag of sugar
• A bottle
• A plank of wood
• A person
• We put the bottle under the wood with the sugar on the load end and the bottle near to the effort.
• We tried to push the load up, it took lots of effort.
• We moved the bottle nearer to the load.
• We tried to push the load up, it took little effort.
We set up slopes with different materials on the slopes (cloth, cling-film, carpet). We predicted how far we thought the cars would travel, taking the force of friction in account. Then we pushed a car down each slope. We measure the distance each one travelled.
We learned that air resistance is a force that slows down a moving or falling object. We learned that streamlined items travel faster as they have less air resistance. Planes are one such streamlined machine. Air pressure also works to help get a plane into the air and keep it there. We made our own paper air planes and tested them to see how far they would travel.