QUESTIONS:

1) What the 6 simple machines:


2) in the case of the lever:
A) How to increase the leverage (to decrease the effort) ?

B) what is the price to pay ? The effort has to _______________ while the load (resistance) ________________________

C) Draw the 3 types of lever

C) When the fulcrum is between the load and the resistance, is it a : first class ? second class? third class?
give an example.


D) A rake is an example of : first class level ? second class ? third class ? draw a rake and the relative
position of the fulcrum, the resistance and the load.

E) a craw bar is a ___________ lever because _____________________________

3) Is the effort decreased by a fixed pulley ?  _____ Why do we use fixed pulley ? ____________________________________

4) Is the effort decreased by a movable pulley ? ________ If you try to pull 100N block using a movable pulley, what is your effort ? _______ N

5) When a machine is used to multiply the effort applied, we say the machine is providing a _________________________

6) You are building a first class lever to lift a 50 kg stone. The total lenght of the lever is 6m. The distance between the stone and the fulcrum (axle) is 1m.
What is the mechanical advantage MA ? (hint : effort arm = distance fulcrum/effort and resistance arm = distance fulcrum/load )
MA = ______________ That means that your effort has been divided by _________. You are stronger because of the machine.
That  means, for your point of view, every thing happens like the stone was only ________ kg.

7) A wheel is 10 cm in diameter , the axle is 2cm. Find the MA = ____________ your effort is divided by _______________

8) a block and   tackle    pulley system has 6 support strings. The load is 120 kg What is the mechanical advantage ? _________
This system divides your effort by ________ and every happens like the load was only __________kg.
------------------------------------------------------------------------------------------------------------------------------