Presentation on theme: "AL-MAHA AL SULAITI SHAHD FAKHROO MAHA AL KAABI GHADA AL NAIMI SCIENCE 8E May The Force Be With You."— Presentation transcript:
AL-MAHA AL SULAITI SHAHD FAKHROO MAHA AL KAABI GHADA AL NAIMI SCIENCE 8E May The Force Be With You
Forces Force is Pushes and pulls. When we are pushing or pulling, lifting or bending, twisting or tearing, stretching or squeezing we are applying force.
Where do we use forces? We use force in everyday situations: Two teams of the players pulling the rope in the game of tug of war We can apply a pull while opening the door of our room. Squeezing wet clothes to remove the water from the clothes. Pushing a wheelbarrow.
Affects of a force A force can do four things to an object; Push Pull Press Twist
Friction Friction is a very common force. Whenever one surface slides over another, friction always tries to oppose the movement. Friction is often a nuisance, because it wastes energy. However Friction allows you to pick up a book with your hands. Our lives depends on friction at the brakes and tyres of cars and bicycles.
Reducing Friction There are a lot of ways that friction could be reduced: lubricating with oil can reduce friction. separating the surfaces by air. Air friction slows down the parachute of a falling man so that he can land safely.
Relationship of Mass, Weight, and Gravity The weight of an object is the gravitational force applied on the object by the mass of the Earth. What this means is that all objects have mass. The gravity of Earth pulls on the mass and we call that weight. Weight = Mass × Acceleration due to Gravity W = MG
Units It is important that, for all of these calculations, the units used correspond with each other. If the distance is given in kilometres and the time in hours, then the measurement of speed should be given in the form of kilometres per hour. This is written as km/h.
Done By: Al-Maha Al Sulaiti Ghada Al Naimi Shahd Fakhroo Maha Al Kaabi Science 8E