Simple Machine Quiz Study Guide. 2.) What is the formula for work? 3.) What is the unit for work?

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1 Name: Work- Simple Machine Quiz Study Guide 1.) Work is when you apply a through a 2.) What is the formula for work? 3.) What is the unit for work? Simple Machines in General- 1.) What are the 2 basic types of simple of machines, of which all other simple machines are variations of? 2.) In general, what do most simple machines do? 3.) When we talk about work being easier, what do we mean by easier work? 4.) A force applied by a machine to an object is the? a.) resistance force b.) effort force c.) force field 5.) A force applied to a machine by a person is the? a.) resistance force b.) effort force c.) force field 6.) Simple machines make work easier, but they actually make more work. Explain how this true, how can they make more work yet make the work easier? 7.) Simple machines make work easier, however there are 2 exceptions to this rule. What are the exceptions, and in each case, what is the advantage each machine gives us. 8.) Group the following words/phrases into 2 categories: Work in Work out Resistance Effort output input Work done TO THE machine Work done BY THE machine Inclined Plane 1.) An inclined plane reduces needed to lift an object by the distance that force is applied. 2.) What did the experiment on page 4 prove? 3.) If the force required to lift a barrel into the back of a truck was 124 Newtons without a simple machine, what would the force required to get the barrel into the back of the truck using a ramp that is 4m long? a.) less than 124 Newtons b.) more than 124 Newtons c.) 124 Newtons

2 4.) If it takes joules of work to lift a barrel into the back of a truck without using a simple machine, how much work would be required to get the barrel into the back of the truck using a ramp that is 4m long? a.) less than Joules b.) more than Joules c.) Joules Lever 1.) Explain, in detail, how you would determine what class a lever is? 2.) What happens to the force needed to move an object as you increase the effort arm? 3.) Would Machines with higher mechanical advantage would take more or less effort force to make something move? A.) more b.) Less c.) the same 4.) Would machines with higher mechanical advantage would take more or less work to make something move? A.) more b.) Less c.) the same 5.) True or False and explain- ALL LEVERS make work easier 6.) Label the effort, resistance and fulcrum in the pictures below an identify what class of lever it is. Pulley 1.) What are the three types of pulleys? 2.) How do you find the mechanical advantage of a pulley? 3.) True or False and explain- ALL PULLEYS make work easier 4.) Find the effort force required to lift the 300 N weight in the diagram above?

3 Wheel and Axle- 1.) The wheel and axle is most like which type of simple machine? a.) lever b.) inclined plane 2.) What would be easier (take less force) to turn and why: An axle with a diameter of 10cm using a 100cm wheel An axle with a diameter of 10cm using a 50cm wheel Why- 3.) What would require the least amount of work to turn and why: An axle with a diameter of 10cm using a 100cm wheel An axle with a diameter of 10cm using a 50cm wheel Why- The Screw- 1.) The screw is most like which type of simple machine? a.) lever b.) inclined plane 2.) Which of the screws to the right (A or B) would require the greatest amount of force to drive into a piece of wood? Why 3.) Which of the screws to the right (A or B) would be the easiest to drive into a piece of wood? Why 4.) Which of the above screws (A or B) would have the greatest mechanical advantage? The Wedge 1.) What does the wedge do as it moves into a material? 2.) Of the two wedges to the right, which do you think would require the least amount of force if you wanted to separate those objects 8cm and why? True or False and Explain! 1- In general, simple machines make less work? 2- In general, simple machines make work easier?

4 3- Single moveable pulleys make work easier? 4- All types of levers make work easier? Calculations: Show your work A clown is trying to lift a refrigerator full of wigs a height of 2M. It would take him a force of 60 Newtons to lift the fridge without a simple machine. 1.) Exactly How much work would be required to lift this fridge of wigs without a machine? 2.) Assuming no friction, how much work would be required to lift the fridge of wigs with a lever that has a mechanical advantage of 6? 3.) Assuming no friction, how much force would be required to lift the fridge of wigs with a lever that has a mechanical advantage of 6? 4.) What is the force needed to lift a magic school bus if you use a lever with a mechanical advantage 25. The force required to lift the dishwasher without a lever would be 1000 N. 5.) How much work is being done by a penguin pushing a purple piano with a force of 50 N up a ramp that is 8 meters long? 6.) What is the mechanical advantage if a unicorn uses its horn as a lever, to open door using 300 N of force, which would normally take about 900N to open (without a simple machine). 7.)How much work is required to lift a bag of cat litter 2 meters, if the bag has a force of 40N. 8.) Melvin the mighty monkey is trying to get a big bag of bananas into his tree house. It takes 90 Newtons of force to lift into a tree without using a simple machine. He then makes the work easier by putting a ramp up to his tree house, which allows him to move the bag of bananas with 10 Newtons of force. What is the Mechanical Advantage of this inclined plane?

5 9.) What is the Ideal Mechanical Advantage of a lever whose effort arm measures 55cm and whose resistance arm measures 5 cm? 10.) What is the Ideal Mechanical Advantage of an inclined plane that has a length of 400cm and a height of 50cm 11.) What is the ideal mechanical advantage for the object below. Show your work 12.) What is the ideal mechanical advantage for the object below. Show your work 15.) What is the ideal mechanical advantage for a lever whose fulcrum is at 20cm? Formulas: Work= Force distance MA = Resistance Force Effort Force I.M.A = Effort Distance Resistance Distance