Systems & Subsystems
What is a system?
A group of physical parts that work together to perform a function.
Name two types of inclined planes.
Ramp and staircase.
What is a force?
An interaction that can change the motion of an object.
What is the formula for work?
W = Force × Distance (W = F × d).
What was the goal of your engineering challenge?
Move a foam ball out of a cup onto a table without touching the ball or cup.
Name one natural and one human-made system.
Natural: Solar system or ecosystem; Human-made: Bicycle or can opener.
What is a wedge and how does it work?
A movable inclined plane that forces objects apart.
Name two types of forces other than mechanical.
Gravitational, magnetic, electrical, tensile, compressive, or rotational.
What unit is used to measure work and energy?
Joules (J).
Name three materials you could use to build your system.
Cardboard, elastic bands, craft sticks, straws, or chopsticks.
What is an input and what is an output?
Input = force/energy/materials put in;
Output = task or service performed.
What simple machine is an inclined plane wrapped around a core?
A screw.
What does the length of a vector represent?
The magnitude (strength) of the force.
What is power and its formula?
Work done per unit time: P = W ÷ t.
What simple machines could be combined for success?
Levers, ramps, pulleys, wheels, or axles.
Give an example of a mechanical system and the type of energy it uses.
Hand pump or can opener – mechanical energy.
What are the three classes of levers based on?
The positions of the effort, load, and fulcrum.
What is the difference between static and sliding friction?
Static holds an object in place; sliding acts as a brake.
If you apply 50 N over 3 m, how much work is done?
150 J.
Give one way to improve a system’s performance.
Use stronger materials or improve alignment of components
Describe the relationship between a system, subsystem, and component.
Subsystems are smaller systems within a system; each has components.
How does a wheel and axle reduce effort?
It allows a small force applied over a long distance to move a larger load.
How does lubrication affect friction?
It reduces friction and heat, preventing wear on parts.
How does mechanical advantage make work easier?
It multiplies the input force to produce a larger output force.
How does testing and redesign show the engineering process?
It allows you to improve a design to meet a goal.