1º Fill in the blanks in these statements.
(a) The two main kinds of structures are _______ and _______ structure.
(b) If a frame structure has no ‘skin’ on it, it is called an ___________frame structure
(c) A structure that relies upon the shape it has been moulded into to give it its strength is called a ________ structure.
(d) Loads can be _______ (non-moving ) or _______ (moving).
(e) Tension, compression, shear, torsion and bending are all types of ____________
(f) All these forces must be catered for in _________structures.
(g) An object is in tension if it is being ______
(h) An object is in compression if it is being_______
(i) An everyday item that cuts using a shear force is a ________
(j) Torsion is a _________ force
(k) If a beam is bent, the top surface is in ___ and the bottom surface is in ____
(l) ____ is a force that tries to stop one surface from sliding against another.
(m) When oil or grease is added to reduce friction, it is called a _________
(n) A long, rigid piece of wood or metal used to support a load across a gap is called a ______
(o) The use of triangles to strengthen a frame is called _____
(p) A common structure often found across water is a ______
(t) Little metal balls that reduce friction and allow bicycle wheels and pedals to move smoothly are called ___
Word: Open frame, Stretching, Static, Shell, forces, Scissors, compression, Beam, Bridge traction, friction, Designing , lubricant, frame, dynamic, twisting, triangulation, bearings
2º Define structure
3º Examples of structure
4º What is a SHELL STRUCTURES. Examples.
5º What is a frame Structure. Examples
6º A example of a _________________ is a brick in a house
7º Write some examples of static and dynamic forces
8º A force tending to compress or reduce something is also know as ______
9º A force tending to stretch a material is also know as _____________
10º Calculate the forces at point A and B.
|Activity: Copy in your notebook this structures. Which of these structures is stable and which is non-stable?. What can you do to make them rigid?.
|Label the sketch to indicate a member that is in tension and a member that is in compression.
||This saw blade is in tension/ compression/shear. Circle the correct answer.
|The rope marked X is in shear/ compression/ tension. Circle the correct answer.
||4. Name the force acting on the material shown.
|Name the force acting on the fabric.
||This rope is in tension/ compression/ torsion. Circle the correct answer.
|The pin shown is in tension/ compression/ shear. Circle the correct answer.
||Identify the forces shown in the sketch.
|9. When bicycle brakes are pulled, the force between the brake blocks and the wheel is a bending force/friction force/shear force. Circle correct the answer.
10. The beam shown is bending under a load. Identify the parts X, Y or Z of the beam which are (a) in compression (b) in tension (c) neither in tension nor compression.