# forces and gravity

• Created by: kamarleo
• Created on: 27-11-17 11:59
• FORCES AND GRAVITY
• What are forces - a force is a push or a pull that objects exert on each other.
• Type of forces
• Magnetism
• Gravity
• Friction
• Upthrust
• Balanced and unbalanced forces
• Balanced forces: There are two machines applying forces to the ice skater. the forces acting on the skater are equal in magnitude and opposite in direction. the forces are balanced, so they cancel each other
• Unbalanced forces: When forces are no longer balanced the object move. Unbalanced forces lead to a change in speed or direction.
• If the forces on an object are balanced: And the object is stationary, it will remain stationary. And the object is moving, it will continue to more at the same speed and in a straight line.
• Resultant force: the sum effect of more than one force is called the resultant force.
• Electrostatic forces
• Rubbing a balloon you can change it and stick it to the wall.
• non-contact forces. these are forces that act between object that are physically separated. Gravitational, electrostatic and magnetic forces is non-contact forces.
• All force involve interactions between objects. there are several different types.
• All types of forces can occur whether the object is moving or not.
• for example, when this crossbow is fired, the force applied cause the bow to change speed.
• when bolt hits the knight's shield, the force change the shape of the shield.
• Gravity is a force that occurs between all objects.
• when you thrown a netball, why does it fall back down?
• The gravity of the earth and the ball pull each object together.
• Gravity is an attractive force that acts between all objects that have mass. The size of the force depends on the masses of the objects.
• Mass is the amount of matter in an object and is measured in kilograms. Mass is not a force. an object, such as this satellite, has the same mass at any point in the universe.
• Velocity and speed. The word velocity and speed are both used to describe how fast something is moving. The difference between these two quantities is that speed is a scale quantity and velocity is a vector quantity.