A structure is any natural, animal or human-made object. All structures serve one of more functions. For example, the function of a bag is to hold various objects. The function of a park bench is to support people while they sit.
100
What is external force?
External Forces are stresses that act on a structure form outside it.
100
While standing on one foot, give 3 examples of natural forces.
wind, rain, snow, vibration, waves
100
What is a gear?
A gear is a wheel that has teeth around its edge. The teeth of one gear fit into the spaces between the teeth on the other gear.
100
What is a pulley?
A pulley is a wheel with a groove in it, and a rope or chain passes over the pulley. The groove keeps the rope or chain from slipping off. One end of the rope is attached to the load and the other end is pulled in order to move or lift the load. Pulleys can be used to lift loads vertically, but they can also be used to move objects in a horizontal direction.
200
What are three types of structures?
Mass Structure, Frame Structure, Shell Structure
200
What is internal force?
Internal Forces are stresses, put on the materials that make up a structure. Internal forces are the result of external forces.
200
A DRAW OFF!
Pick a person from the other team and you are both going to draw what the teacher tells you. The team that gets it first, gets the points.
200
If you turn one gear clockwise, what way will the next gear turn?
When you connect several gears in a row, you are creating a gear train. When a force makes any one gear turn, all the gears in the gear train will turn. Each gear turns in the opposite direction to the gears beside it.
200
What are the two ways that pulleys are used?
Pulleys are used to change the direction of a force, and/or to make it easier to lift a load.
300
Name 3 different man made structures.
buildings, chairs, benches, bridges
300
What is a dead load?
Dead load is a permanent force acting on a structure. Over time can cause the structure to sag, tilt, or pull apart.
300
Explain one of the experiments we did in class and what you learned from it.
load - bridge, internal force - sponges, external force - structure
making pulleys, making gears
300
What are the four types of gears?
The spur gear, bevel gear, worm gear, and rack and pinion
300
Describe a fixed pulley.
A fixed pulley does not make it easier to lift a load, but it does change the direction of the force. A fixed pulley has one wheel that stays in place. Fixed pulleys do not give people more power. They only help people move things vertically or horizontally. Flagpoles have fixed pulleys for raising and lowering flags.
400
Name 4 animal made structures.
dams, behives, webs, spiderwebs, nest,
400
What is a live load?
Live load is a changing or non-permanent force acting on a structure, for example, snow, weight of vehicles or people.
400
CHARADES!
Pick a person from the other team and the two of you will act out what the teacher tells you, the first team to guess wins the points.
400
If the first gear in a gear train has 8 teeth and it turns three times for every one turn of the second gear, How many teeth should the second gear have?
The second gear should have 24 teeth.
400
Describe a moveable pulley.
A moveable pulley makes it easier to lift the load (you only need half the force), but it does not change the direction of the force. A pulley tied to the load itself is called a moveable pulley.
500
Name 3 different natural made structures.
mountains, stem of a flower, tree
500
Name the five types of internal force. Bonus 500 is you can explain each five types.
Tension forces – stretch the material by pulling its ends apart. Shear forces - bend or tear the material by pressing different parts in opposite directions at the same time. Compression forces – crush the material by squeezing it together. Torsion forces – twist the material by turning the ends in opposite directions. Bending forces - a combination of tension forces and compression forces that result in a structure temporarily curving.
500
When writting about an experiment what do you include?
purpose (what we want to find out), hypothesis (what we think will happen), materials (what we used), method (what we did), conclusion (what we found out)
500
Name five ways we use gears in our daily life.
bicycle, clocks, blenders, can openers, motors, jack for a car,
500
Name 5 ways we use pulleys in our daily life. Bonus 500 if you can name 3 more!
flag pole, crane, weight machine, cloths line, window cleaner seat, elevator, hoist for an engine, water well, conveyor belt,