science- physics

• Mechanical system

  Composed of physical parts working together, for example, a bus
• Many systems in society include both mechanical and non-mechanical systems
• In robotic surgery, a machine operates on a patient under the control of a surgeon at a console
• Components of a system


  • Individual parts or procedures that work together to perform a task or function
• Force in science is defined as a push or a pull that acts on an object
• In the future, automatic surgery may be possible with robot systems performing surgery without direct human input
• Non-mechanical system


  A set of procedures, methods, or rules that accomplish a task
• Society runs smoothly and efficiently because of its many systems
• Surgeons have better precision and dexterity with robotic surgery, as well as full stereoscopic vision
• Society needs to assess the ethical and acceptable implications of automatic surgery in the medical system
• Objects being pushed or pulled experience a force
• Some systems, such as the solar system, occur naturally
• Categories of systems

  • Mechanical systems
  • Non-mechanical systems
• Remote surgery allows surgery to be done with the surgeon and patient in different locations
• A system is a group of individual parts or procedures that work together to accomplish a desired task
• Minimally invasive surgery (MIS) means less trauma and pain for the patient, who recovers more quickly
• Systems are made up of individual components that work together to perform a task or function
• Forces can stop objects from moving, such as when you catch a ball
• Your chair seat is pushing upward on you so that you do not fall
• Most force meters contain a spring or elastic component that stretches or compresses when a force is applied
• Action-at-a-distance forces

  • Gravity
  • Static electricity
  • Magnetism
• Mass does not change as a result of gravity
• As you sit at your desk, you are being pulled to the ground by Earth’s force of gravity
• Classifying Forces


  1. The football begins its motion as a result of the force of the player's foot

  2. All the different forces shown can be classified as contact forces or action-at-a-distance forces
• If you have a mass of 50 kg on Earth, your mass on the Moon is still 50 kg
• The metric unit for force is the newton (N), named after Sir Isaac Newton
• When we let go of a ball, it is pulled to the ground by the force of gravity, even though nothing is touching it
• Gravity


  The attraction between two objects due to their mass
• Mass is the amount of matter in an object
• On Earth, a 1.0-kg mass has a weight of 9.8 N
• Weight is the amount of force on an object due to gravity
• Contact forces

  • hitting a tennis ball
  • friction
• The amount of attraction between objects due to gravity depends on each object’s mass and the distance between them
• Most scales marked in kilograms measure mass, not weight in newtons
• Even objects at rest have forces acting on them
• Weight changes when the force of gravity changes
• Calculating the Force of Gravity (Weight)

  1. Mass and weight are directly proportional

  2. On Earth, weight can be calculated by multiplying mass by 9.8 N/kg, which is Earth's gravitational field strength symbolized by g
• Energy is the ability to do work
• In science, work is the amount of effort spent when a force causes an object to move a distance
• Energy is defined as the ability to do work