Edexcel IGCSE Physics: Double Science 复习笔记：1.2.1 Types of Forces

• Forces can affect bodies in a variety of ways:
  • Changes in speed: forces can cause bodies to speed up or slow down
  • Changes in direction: forces can cause bodies to change their direction of travel
  • Changes in shape: forces can cause bodies to stretch, compress, or deform

   

The effects of different forces on objects

• There are many types of force. Some examples include:
  • Gravitational (or weight) - the force between any two objects with mass (like the Earth and the Moon)
  • Electrostatic - the force between any two objects with charge (like a proton and an electron)
  • Thrust - the force pushing a vehicle (like the push from rocket engines on the shuttle)
  • Upthrust - the upward force on any object in a fluid (like a boat on the surface of a river)
  • Air resistance (or drag) - the force of friction between objects falling through the air (like a skydiver in freefall)
  • Compression - forces that squeeze an object (like squeezing a spring)
  • Tension - forces that stretch an object (like two teams in a tug-of-war)
  • Reaction force - the force between any two objects in contact (like the upwards force from a table on a book)

   

Several types of forces acting on different objects