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Pulleys
grade 3/4
Question | Answer |
---|---|
What is effort? | The work needed to move a load |
What is force? | A push or a pull on something to move it |
What is a spring scale used for? | To measure the effort needed to lift a load in newtons |
What kind of pulley is attached to a structure? | A fixed pulley |
What is a problem with a fixed pulley? | You are lifting the whole weight of the load |
What is the load attached to in a movable pulley? | The load is attached to the pulley |
What is a problem with a movable pulley? | You have to pull up to lift the load |
What pulley system lets you pull down on the rope and cuts the weight of the load in half? | Combined pulley |
How do you find the mechanical advantage of a pulley system? | You count the number of supporting ropes |
What two pulley systems cut the weight of the load in half? | Combined pulley and movable pulley |
If the gear you turn goes clockwise, what direction does the second gear go? | Counterclockwise |
What direction does the effort force go in a fixed pulley? | Pull down |
What direction does the third gear in a gear train go if the first gear turns clockwise? | Clockwise |
If the gear you are turning is large, and the second gear is small, which gear turn faster? | The small second gear |
If the large gear has 20 teeth, and the small gear has 10 teeth, how many times will the small gear turn when the large gear turns once? | Two times |
If the gear you are turning is large and the second gear is medium, which gear turns slower? | The large first gear |
What is the name of gears that work on a flat surface? | Spur gears |
What is the name of gears when one is flat and the other is upright? | Bevel gears |