Question | Answer |
What is a Structure? | Anything made of parts put together for a particular purpose (or purposes) |
What is the difference between Form and Function? | Form: the shape and physical appearance of a Structure
Function: the task or purpose of the structure |
What is Force? | A push or a pull |
What is the definition of Gravity? | The force of attraction between all objects |
What are the effects of Gravity? | -Gravity that pulls objects of small mass together is weak *is noticeable when at least one of the objects has a large mass. *Gravity of objects w/ very large mass (earth) can move object w/ small mass (eraser) large distance- why objects fall to ground |
What is the difference between Applied and Non-Contact Forces? | Applied Forces: forces that push or pull objects when objects come in contact with one another
Non-Contact Forces: forces that push or pull things without contact |
Examples of Non-Contact Forces | *Gravity
*Magnetic Force (forces that pull two magnets together
*Electrostatic Force (the force that causes static cling) |
Examples of Applied Forces | *Feet putting downward force on bike pedals
*Oar of boat striking the water
*Baseball bat striking a ball |
What is the difference between Mass and Weight? | Mass: the quantity of matter in an object
Weight: the force of gravity acting downward on an object |
What instruments are used to measure mass? | Balance and a scale |
What instruments are used to measure weight | Newton Spring Scale
**because weight is a measure of force, it has a magnitude and a direction. We might say that a mass of 1 kg had a weight of almost 10 N downward |
What are the units used to measure mass? | Grams (g) and Kilograms (kg) |
What are the units used to measure weight? | Newtons (N) |
What are 2 different ways that we can describe force? | 1. DIRECTION OF FORCE: up, down, left, right or sideways. in diagrams the direction of arrows shows the direction of force
2. MAGNITUDE OF FORCE: strength of force (greater/lesser) in diagrams the thicker the arrow the greater the magnitude |
What is Load? | A force acting on a structure |
What is a Static Load? | Loads acting downward on structures that result from gravity |
What are 2 classes of Static Loads? | 1. DEAD LOAD: the weight of the structure itself
2. LIVE LOAD: the weight of the objects that a structure supports |
What are Dynamic Loads? | Loads on a structure that are caused by forces other than gravity |
What are some examples of forces that act on a structure to create dynamic loads | Moving water
High winds
Car striking guardrail
Baseball bat hitting ball |
What is a Solid Structure? | Strong structure relying on solid construction materials to support loads. They have a large mass. A well made structure can last for a very long time |
Examples of a Solid Structure | -Concrete Dam
-Wooden telephone pole
-Marble Statue |
What is a Frame Structure? | Uses a network of materials that support each other. A single part of structure cannot support the mass of structure by itself. Individual parts are connected & require special support so they don't bend/collapse. Widely used, sturdy, lighter than solid |
Examples of Frame Structures | -Body's skeleton
-Goalie's net
-Spider web
-Network of steel or wood beams supporting a bridge or building |
What is a Shell Structure? | Hollow, curved shape. Can be very light and yet have a great deal of strength and rigidity. |
Examples of Shell Structures | -Bird's beak
-pop can
-bike helmet |
What is a Combination Structure? | Structure containing various solid, frame and shell components |
Example of a Combination Structure | THE HUMAN BODY
FRAME: Human skeleton (bones that hold muscles, tendons & ligaments)
SHELL: Skull (curved, hard and hollow)
SOLID: Femur (large solid bone located in thigh) |
What is Internal Force? | Forces acting between two parts of a body |
What is External Force? | A force acting on an object or structure from the outside |
What are some examples of External Forces that act on buildings? | -Wind
-Earthquake
-Weight of people in a building
-The weight of the building |
What is the difference between
Point of Application and
Plane of Application of Force | POINT OF APPLICATION OF FORCE: the location of an object where the force is applied
PLANE OF APPLICATION OF FORCE: An imaginary flat surface through which the applies force passes |
What is Tension Force?
Examples | Internal Force pulling the particles of an object apart.
Example: Trampoline, guitar strings |
What is Compression Force?
Examples | Internal Force that presses or squeezes the particles of an object together.
Examples: Mattress springs (when you lie on the mattress), laying your head on a pillow, stepping on the sole of shoe |
What is Torsion Force?
Examples | Internal twisting forces created in an object as a result of a twisting motion being applied to the object. Can be created when both ends of a structure are twisted or when only one end of structure is twisted
Ex: ringing out a wash cloth, door knob |
What is Shear Force?
Examples | Internal force acting on an object as a result of pushes/pulls in opposite directions usually causing rips or tears. Ex:: scissors, a strong wind blowing horizontally against a tree causing shear force inside tree, can cause it to bend or break. |