8TH GRADE - Systems Unit Test - Ms. Lieu.

What is a system?

A system is a group of components or processes that work together to meet a need or perform a goal.

Two main types of systems?

Physical systems and social systems.

Examples of physical systems?

Mechanical, body, optical, mass transit.

Examples of social systems?

Schools, Indigenous clan systems, healthcare systems.

What is a mechanical system?

A system made of simple machines working together.

Example of a mechanical system?

Elevators using pulleys.

What is a body system?

Organs working together to keep the body alive.

Example of a body system?

Skeletal system (bones, muscles, joints).

What is an optical system?

A system that uses light to improve vision.

Example of an optical system?

Glasses or contacts bending light.

What is a mass transit system?

A system that moves large numbers of people.

What is an Indigenous clan system?

A social system where members share customs, languages, and roles.

What is the purpose of a system?

What the system is meant to do.

What is an input?

What goes into a system to make it work.

What is an output?

What comes out of a system after it works.

Example of input/output for a toaster?

Input: electricity. Output: toasted bread.

What is force?

A push or pull measured in Newtons (N).

What is energy?

The ability to do work.

What is work?

When a force moves an object a distance.

 Formula for work?

W = F × d.

What do simple machines do?

They make work easier by reducing the force needed.

Name the 6 simple machines.

Lever, inclined plane, pulley, wedge, screw, wheel & axle.

Example of a lever?

A seesaw or screwdriver.

 Formula for mechanical advantage?

MA = Fout / Fin.

What does MA > 1 mean?

The machine makes work easier.

What does MA < 1 mean?

More force is needed, but you gain speed.

What is friction?

Rubbing between parts that produces heat.

How do lubricants help?

They reduce friction so parts glide smoothly.

What is efficiency?

How well a system turns input energy into useful output.

Why do cell phones evolve?

Changing social needs, busy lifestyles, portability, and new technology.