Real Life
An astronaut on the Moon has the same ___ but a different ___.
Mass, weight
The term for the quantity of matter in an object, commonly measured in grams or kilograms
List two non-contact forces
Gravity, magnetic force, electrostatic force
What type of structure is a bicycle? Explain.
A bicycle is a frame structure because it is made of connected tubes that form a rigid skeleton to support the rider.
What is an internal force?
A force acting between two parts of a body.
A gentle push vs a hard shove changes this aspect of force.
Magnitude or strength
Which term is measured in Newtons?
Weight
What are two examples of external forces?
Wind, earthquakes, weight of building, weight of people inside buildings, gravity, etc
What type of structure is a brick? Explain.
A brick is a solid structure because it is made of solid material throughout and supports loads by its mass.
Define Compression
An internal force that presses or squeezes the particles of an object together.
A concrete sidewalk cracks under heavy pressure. This shows weakness in resisting which force?
Compression
What is a dynamic load?
A force (not gravity) acting on an object
Define an external force.
Define a frame structure
A network of parts that supports loads
The force that acts when an object is twisted.
Torsion
A bookshelf collapses because too many books were added. Identify the type of load that caused the collapse.
Live load
Explain the difference between live load and dead load
Live - weight of itself + something else
Dead - weight of itself
What is the difference between point of application and plane of application?
The location on an object where the external force is applied or concentrated is the point of application. The plane is the imaginary flat surface through which the force runs through.
What is a shell structure? And give an example
A hollow, curved, and strong structural design
The internal force that is a result of pushes and/or pulls in opposite directions
Shear force
You push on a door right next to its hinges, and it barely moves.
Which characteristic of force are you failing to use effectively?
point of application
What is the difference between mass and weight?
Mass - amount of stuff something is made of
Weight - gravity acting downwards on an object
Why are we not being pulled down to earth's core because of gravity?
The magnitude of the downward force (gravity) equals the magnitude of the upward force (stool on you), meaning that you can sit still.
What is the difference between the function and the form of a structure?
The form is the shape and physical appearance, and the function is the task or purpose of a structure.
Name the 4 types of internal forces
Shear, compression, tension, torsion